Patch 4.05 Machinist Rotation: To Overheat or Not to Overheat? Here are my findings.

[Leticro]

I've realized a lot of people are looking for MCH guides and there hasn't been any posted so I felt the need to share my findings. There is a TL;DR (which is also a good summary) below for how to use the overheat mechanic.
For an entire day or two, the logic just didn't seem to make sense to me so I spent these days just crunching a ton of numbers and here are my findings for the logic behind how the Overheat mechanic works in the rotation.

Logic for the rotation: The following numbers are just an example, but imagine for 20 sec there's an option between a 10% AVERAGE damage buff, or a 15% CONTINUOUS damage buff. Since you can have a full 15% for the whole 20 seconds, that generally seems like the better option of course.

However with a 10% AVERAGE where you can control say a 20% increase the first 10 sec, and a 0% increase for remaining 10 sec (10% overall average), and you can put all your damage in that initial 20%, then overall damage of using the 10% buff would beat the 15% damage buff.

Overheating uses this concept, where when you overheat, you choose the 10% buff over the 15% buff in order to control the damage window so you can buff the hardest hitting hits you have in the 20%, in exchange for having absolutely no buffs when you don't have extra damage moves to pop. The 20 seconds essentially is representing the entire fight in terms of how you can have 15% damage buff the whole fight with the heated combo by not overheating, or have 10% buff average with moments where there's no buffs (gauss barrel removed), but moments with 20% buffs (overheated wildfires).

The gain is so small though that you can only get like 1% extra damage out of it since having a continuous 15% buff is logically the better option. Having a couple off-GCDs for your overheat/wildfire window would equal the same value as not overheating, and any more than a couple would be a small increase in overall damage, but the gain is so small even when done correctly (literally about 30 potency per minute) when not combo'ed with hypercharge.

Here is a spreadsheet of my number crunching of using a wildfire mid combo if it makes sense to you. The combo may not be the most optimal, but it's what I currently think is efficient, and it is only used as a test to compare overheating vs. not overheating.Hypercharge is not included in the calculations because if it's good to overheat without hypercharge, it's obviously better with hypercharge. The first sheet is a test rotation comparison, and the second page was just used to come up with the logic of how overheating gets more damage even though it creates a lower overall damage buff.

The spreadsheet also does not include an opener or anything, but you would start with 50 heat. Many people use the flamethrower to build up heat to get it to 90, and if you do that, then you could maybe overheat with the initial wildfire. However, using the low potency flamethrower for a 1% increase seems excessive, though it is probably still a slight increase in overall damage. However if your heat is not 90+ by the time your wildfire is ready, I'd recommend just using the wildfire and not overheating to avoid the down time of heating, thus my initial wildfire would not be overheated if I avoid flamethrower.

Other tips: Overload at the end of every hypercharge now that the 800 potency is equivalent to the 30s cooldown. Hypercharge should be before every wildfire, but overload doesn't have to be in wildfire since it doesn't count towards wildfire damage. Executing the rotation perfectly should have literally every off-GCD always on cooldown after the initial rotation since they're all on a 30 sec, 1 min, and 2 min cooldown system, but we're not perfect and mechanics can interrupt things.

Ricochet, Rapid Fire, Reassemble all share cooldowns with wildfire so they should be used in every wildfire, but you probably already know this. Just using those GCD's for an overheated wildfire should already yield slightly higher damage if not equal damage than a non-overheated wildfire, and of course even more so if done with hypercharge.

My opinions: Crunching all these numbers is ridiculous just for a rotation. Also being able to comprehend the concept of an overall 10% damage buff being better than an overall 15% damage buff (just an example, not actual percentages) is way too advanced just to find out how to play a job. Though ridiculous, I actually enjoyed doing all this math just to figure out the best rotation. The math made it feel like I was actually doing engineering to figure out how to use Machinist, which has the tech savvy or engineering feel, and thus fitting the theme of a Machinist! I see many forums about how weak MCH is and how the updates are crap because it didn't benefit the job at all, and I agree, but I also don't think this was entirely the wrong move. BRDs are significantly easier to use for high damage while MCHs have to do everything perfectly if we want to have a chance to match their damage which is entirely unfair not to mention we have less utility now that it's shared in role actions, but I still like how MCHs play regardless. However please buff MCH a bit more because I want to be rewarded all this hard work XP

These results are something I came up with in a day or two, and I'm only one person so parts could be inaccurate. Feel free to rebuttal in comments and all that. Rotation guides might come out soon to prove my numbers entirely wrong or completely enforce what I said with different numbers. If you're making a rotation guide, feel free to use this as a source!

Thank you Fannah and Elnidfse for the feedback in the replies for more accurate numbers! Also Elnidfse's math resulted in a single extra auto-attack by overheating and does not recommend going for the overheat damage since it is so insignificant. After their changes, my math went from 5% max down to less than 1%!

TL;DR: This guide doesn't have an opener, but it hasn't changed much from other guides. Overheating during every wildfire yields about a 1% increase in damage without hypercharge in my math, which isn't much (literally about 30 extra potency per minute), but is an increase every wildfire if it doesn't mess you up. Since the overall damage is so small, I recommend just overheating with hypercharge because it's easier to manage so that it doesn't require you to pre-plan your procs and rotations to line up with the wildfire (getting the 90+ heat). This is important because most of the time, it's at like 85 heat or just doesn't line up when wildfire is ready again, and waiting for the wildfire is a waste so only overheat if you're in a good position to. However I noticed the Dragoon teather shares the same cooldown with the wildfires, so if you buff it like with hypercharge, trick attack, DRG tether, etc. and you're comfortable with overheating, then line the heat up and do it.

[KDSilver]

Edit your post to bypass the limitation.

[Leticro]

Thank you so much for that! But I screwed up deleting the multiple posts so it shows all those deletes as blanks now lol

[Myon88]

It's late so I can't look through all that math, but yes you're pretty close to mark. Some of us have looked over the numbers elsewhere and basically even if you overheat a wildfire (as intended?) you gain such a minuscule amount of damage over pretending overheating doesn't exist at all, that I'm really not quite sure how they thought this was okay from a tuning standpoint.

[Elnidfse]

It's late so I can't look through all that math, but yes you're pretty close to mark. Some of us have looked over the numbers elsewhere and basically even if you overheat a wildfire (as intended?) you gain such a minuscule amount of damage over pretending overheating doesn't exist at all, that I'm really not quite sure how they thought this was okay from a tuning standpoint.

It ends up being 8 potency per overheat (net-wise). Over a 10 minute fight you'd do as much as a single auto attack.

The only reason to bother would be to sync up your cooldowns I suppose.

[Caitlyn]

You gain 10% more damage for overheat for 10s, but gain 0% more damage after overheat vor another 10s + no heated combo for 10s, which is also a loss of 30 potency for the next 3 skills. Especially you have to put your GB back on your gun manually.

No, I dont recommend to overheat, other than for AoEs or shortly before phase transitions.

[Leticro]

That's why it took me multiple days to figure out the actual math for, of which you can see in the spreadsheet. Its actually better to overheat because you get more damage out of it overall! As explained in my initial post, the logic for it is that the though there is a better overall damage buff on average by not overheating, we overheat because it allows us to control a specific window for an even higher buff, even though it's less overall damage on average. Being able to output our off-GCDs in that window is how overheating allows for higher net damage.

[Fannah]

Elnidfse, I found 132 and more per overheat (by using the most easy rotation, without conditions, and so the lowest possible, so we can do way better). I'm wondering how you do to get only 8 (I even already made a post about it).
Caitlyn, the bonus from the 10% is multiplicative and you also have to count the bonus dmg counted thanks Gauss Round and Ricochet during it. The whole makes the loss of the GCD smaller than the gain.

Now we can say that 132 potency and more is underwhelming for a 60sec CD. It's still a more huge gain to burst on the moment of 307 potency minimum.

+0.0s : Hot shot to overheat + Rapid Fire / Reload / Wildfire
+3.0s : Combo 2 (255P -> ammo) + Reassemble
+4.5s : Combo 3 (295P[crit] -> ammo) + Ricochet (300P)
+6.0s : Cooldown (255P -> ammo)
+7.5s : Cooldown (230P) + Gauss Round (200P) (so the next Gauss Round will be when the Gauss Barrel will be up)
10.0s : Cooldown (230P)
----------------No more overheat nor Gauss barell-------------------
12.5s : Quick reload + Combo 1 with ammo
15.0s : Combo 2
17.5s : Combo 1 or 3
20.0s : Combo 1 or 2 + Gauss Barell + Barell Stabilizer -> 50 Heat

Total potency while Overheating (and I don't even count Hypercharge, nor the crit, nor the ally bonus, nor Auto attacks, nor a well placed Overheat where the boss end to being untargetable during some sec) :
(255+295[crit]+300+255+230+200+230)*1.05*1.1*1.08*1.25 = 2752potency.
1.05 = Gauss Barrel.
1.1 = Overheat.
1.08 = Hot Shot.
1.25 = Wildfire.

Then during the phase you don't have Gauss Barrel anymore (let's say you have no lucky proc) :
(185+200+160+160)*1.08 = 761potency

So during all that time, we have 2752+761 = 3513 potency.

Without overheating, you can't spam the same way your Cooldown, so you will have to do the 3rd GCD as a Combo 1 instead, then Combo 2 + Cooldown, so you have 50% to have 40 less total potency :
(255+295[crit]+300+215+230+200+230)*1.05*1.08*1.25 = 2445P (2501 if you have the proc for Combo 3)
During the 10sec after still with 50+ heat :
(215+230+190+190)*1.05*1.08 = 936potency
2445+936 = 3381potency

Total potency difference :
3513-3381 = 132 potency.

Pure burst phase difference :
2752 - 2445 = 307 potency.
(for others who know my result with 149 potency, I didn't optimized the 10sec phase without Gauss Barrel, giving a slight advantage to the non-overheating one).

[Leticro]

It ends up being 8 potency per overheat (net-wise). Over a 10 minute fight you'd do as much as a single auto attack.

The only reason to bother would be to sync up your cooldowns I suppose.

In my spreadsheet I got about a 400 potency gain per minute, so it'd save you a whole weaponskill or 2 (assuming 0% chance of procs), though that also means you somehow execute your skills perfectly of course, but that can be significant in savage because over a 10 minute fight, thats roughly an extra 30 sec or so of damage. (400 is roughly a GCD and an off-GCD average, and 2.5 sec per GCD)

[Fannah]

Leticro, what is this 355 potency on your Slug shot (combo 2) ? The skill does 230+25 with an ammunition, so 255. Did you take something else in count to speak about 355 potency? You meant 255 potency right?

And your 603.65 potency for the Clean Shot + Gauss Round? 270+200 = 470 potency. I don't see what you did to get a bonus of 28%+ on it