I see a fairly diverse amount of feedback from various players when it comes to Shadowbringers job direction, so my suggestion included a few other considerations Namely it tries to hit a few notes.
1. The RDPS>PDPS supporters
2. Not alienating the PDPS=RDPS jobs.
3. Re-emphasizing a burst window (Though not necessarily a 120s mystic alignment)
4. Minimizing the impact / tuning needed in the world at large (Since this would literally be for the benefit of Savage and Ultimate only)
5. Encourage party diversity (AKA not hard lock a comp)
In my opinion, the blurb from the previous page aims to accomplish all that.
This is going to be a lengthy one, and we'll be using some arbitrary number values to illustrate the concept.
Quick Primer: RDPS vs PDPS
RDPS or "Raid DPS": This is the baseline damage that the job brings to a group. This includes personal DPS and all DPS given by buffs and minus all DPS taken by buffs.
PDPS or "Personal DPS": This is the end amount of damage sourced from your character, including all buffs.
Defining "Out of the Box": I've been using this term, but basically this is raw RDPS the job does assuming a raid size of 1. Therefore, an 'out of the box' RDPS value of 12,000 with Ninja whose trick attack brings on average 2% bonus RDPS has a PDPS value of about 11,760. If Trick attack was an average RDPS increase of 10% (which is like, the same as having 5 dancers), then its PDPS is around 10,800.
To illustrate just how ridiculous that would be in practice, any job that increases the raid's total DPS by 10% would, at the suggested numbers to follow, have to have a PDPS of around 3,000.
A ton of gobblygook.
Let's use the first example first, with a balanced team of two tanks, two healers, and one of each type of dps (Melee, ranged, caster, cannon). We'll use tank = 7500, healer = 5500, and DPS = 12,000 'out of the box'. The total raw RDPS = 74,000.
We'll say each of the Melee, ranged, and casters are the same weight - on average, the support is worth about 2% more RDPS and it always lines up cuz magic. 74,000 * 1.02^3 = approximately 78,529. With a Cannon, you double that RDPS increase for them, netting an additional 749 DPS. 79,278.
Let's say instead of the cannon we add another melee. The same calculation is 74,000 * 1.02^4 = 80,099.
Not bad, it's pretty close.
A small differential, but with the additional role we have yet another tuning lever in the attribute bonus. Team 1 has all roles represented and Team 2 has not.
Lets apply a 1.08 (representing 8% attribute bonus) to team 1 and 1.05 to team 2.
Team 1: 85,620
Team 2: 84,103
What about a double cannon team?
Team 3: (74,000 * 1.02^2 + (24000 * 1.02^2 - 24,000) ) * 1.04 = 81,077
All of this assumes 100% performance by everyone involved. Supposedly SE tunes in unupgraded Tome Gear and slashes that maximum performance, but I can't say for certain. Titan is currently around 75,000 or so, so lets apply a "Casul tax" and slash our totals (We'll assume the presented numbers in this system are in i450 unmelded) by about 15%.
Team 1: 72,777
Team 2: 71,487
Team 3: 68,915
No week 1s for anyone. A fully pentamelded set (we'll use DH because it's easy) over a 0 meld set is an extra 2180 stat points. With DH, that's 36.33% direct hit chance or about 9.075% more damage. Pentamelded team looking like
Team1: 79.872
Team2: 78,456
Team3: 75,634
Week 1s for many people, though multiple cannon jobs are taking a nasty hit.
What if we applied the increased cannon buff to attribute bonus as well from the party system?
In Team 1 we see an increase from 14,578 to 15,658. Total gain 1,080.
In Team 3, we see an increase from 13,498 each to 14017. Total gain 519 each. Still rough for them.
What if the "Cannon buff" itself was a flat 3% rather than being a full house bonus?
In team 3, we see an increase from 13.498 each to 13,757. Even worse.
...Both?
13,498 to 14,536 each. Total increase of 2077.
Team 3 100% total: 83154
Team 3 casul tax total: 70,680
Team 3 pentameld: 77,572.
Summary
System Change
New Role: Cannon. Jobs in this role gain double the effect of party buffs and enemy vulnerabilities, and role attribute bonus.
"Normalized" RDPS and PDPS levels.
Team composition
Team 1 (2 tanks, 2 healers, 1 of each dps role)
Team 2(2 tanks, 2 healers, no cannons, 3 other roles covered)
Team 3(2 tanks, 2 healers, 2 cannons, two other roles covered)
Theoretical Maximum
Team 1: 86,700
Team 2: 84,103
Team 3: 83,154
'Minimum ilvl tune'
Team 1: 73,695
Team 2: 71,487
Team 3: 70,680
'Pentamelded'
Team 1: 80,880
Team 2: 78,456
Team 3: 77,572.
It's late, but you get the idea. These three team set ups cover a fair range of party compositions (though obviously not all), but as a parting note, it seems if we do the doubled attribute buff and cannons adding a flat +attribute bonus rather than being a full set bonus, the stat bonus could be reduced.