Having higher level gear shouldn't BREAK coil runs!!!

[Hiruke]

That's caused by multi-dotting/dpsing levi too hard WHILE the spumes are up. At this point you're clearly supposed to bring your dps on the spumes and not levi himself (ofc some classes gain a higher dps if they also multi dot on levi for example). But you're definitly not forced to do a full dps stop like in ifrit.

I think it's safe to say that any SMN would feel it's more efficient to continue to dps Leviathan as you take down spumes, by using Bane to spread DoTs to both the head and the tail. BLM might also think Flare is more efficient when at the end of a Fire cycle, to hit both head and spume. One would think that better gear/higher dps would make fights easier, rather than "more difficult". This even happens in dungeons. Haukke Manor (Hard), for example, if you are too efficient with AoE attacks on the succubi that pop out and take the boss too low, boss will instantly eat sub boss when she pops, causing instant wipe.

There are two key components to this:

1) For Leviathan EX in particular, mirror and mount are 1% drop rate. Presumably you will far surpass desired iLVL for this fight long before you get either item, causing lots of unintended problems as you dps way too hard (or I guess in more cases, full carry the rest of your team because their dps is garbage - though thanks to no parsing, they probably think they are heroically amazing).

2) SE clearly believes adding more damage makes fights easier, period, as evidenced by their implementation of the Echo. If people who actually already are clearing things like Second Coil are tripped up by doing too much damage, how might the casuals respond to this? Especially before HP % was displayed, Binding Coil Turn 5 was quite a bit when not doing the exact right amount of dps during Conflagration. Think the casuals had a good time figuring out how the fireballs worked, or think they eventually lucked out/got carried/gave up?

Just because it's been around for awhile, doesn't make it good design. It's bad design in WoW, and bad design here.

Fully agreed. While I think it's relatively easy to circumvent the nonsense that occurs from dpsing too hard, it's clearly not a good way to keep subs, as casuals and the people from WoW who were only good because of DBM (as opposed to the people who were good because they could pay attention) get tripped up by mechanics just as they stand, and get tripped up WAY MORE when phases push early. You still can't pull off even a Garuda EX in DF without queueing for hours, and that content is dead easy compared to most everything else.

Every piece of content we've had so far (bar Ramuh) has been built before players had access to HP percentages without the use of third party tools. Think about that for a moment.
I cannot believe the devs built content thinking "Well, at this point in the fight, the party will look at their third party tools and all stop DPSing at 61%. Yeah, that's a great idea.
It's clear that no thought was really put into this, when you look at content and realise the only way to properly measure and approach phase changes was through the use of third party tools.
Also, "Controlling" DPS is a myth, because all that means is forcibly limiting yourself, either by using a poor rotation (which is just stupid to think the devs want us to play poorly), or to literally stop attacking.

Agreed. This was SUPER fun for Twintania. "Hey guys, we're coming up on a phase shift, might want to hold back? Not sure though, because, well, it's at UNKNOWN PERCENT health." Dev team doesn't seem to want to recognize that seeing hp % and being able to parse and see actual damage is what allows people to figure out how to improve enough to get stuff done. If you can't figure out which rotation does the most damage in each situation, you are definitely performing sub par, and at any hard dps check, you're either getting carried or failing miserably. It's amazing to roll into dungeons (DUNGEONS) with people who are full i110 gear and still do less damage than you did at i55 because they think they know how to play the game but clearly do not have any clue (ex., the staggering number of BLMs who WILL NOT cast Flare when fighting 5-10+ enemies because "Flare is not good"... you serious, guys?).

Sad thing is, if their dps would be really that high they wouldn't have that much problems. At a certain point voices will align perfectly again, in T8 it's only between two certain points that field + towers getting unsynced after you pass this point they're perfectly fine again. And for other fights like primals, if you have the dps to push them you also have the dps to handle multiple adds at the same time etc.

As above, I agree that if you have the dps to push phases early, you have it within your power to compensate. However, also as above, this completely ignores the casuals, that SE clearly cares about, because the way SE wants to push the casuals through is a (huge) flat increase in damage, which will absolutely cause all sort of phase shift hilarity that they clearly can't account for. Current design is only ok if SE agrees to stop caring about casuals and only design for hardcore (in which case, please add dps meter, SE, thanks) - which I'm fine with, but SE clearly is not. They are under mistaken assumption that they can only make money by pandering to people who can't actually play the game (and who will most likely leave in under a year because something newer and shinier has been released).