
Originally Posted by
Sylvant
I...think you're confused how Spell Speed and the the Attunements work? The attunements, regardless of which is being used, are limited to a set number of casts; four for Garuda, four for Titan, two for Ifrit. You can have max Spell Speed and that won't change the damage output of these attack phases.
For math purposes (assuming you're at 90, single targeting, and every attack hits entirely);
Garuda deals 1500 potency of damage during her phase.
-580 potency on Slipstream (430 + 150 dot)
-920 potency on all four casts of Emerald Rite (230 x 4 casts)
These numbers are only affected by things like damage variance, Determination, Critical Hit, etc. Spell Speed only affects how quickly you move through the phase.
On to the topic of downtime; having cleared every Extreme and normal trial fight so far on Summoner, I can safely say I haven't really had any issues with it. The fights are structured around a similar timer that damage windows are on (60s, 120s, 180s, etc), believe it or not. You can use Searing Light to gauge where you should be in your rotation. If skipping a couple of the attunements is what you need to do to keep everything lined up, it's probably best to skip them.
If anything, Spell Speed is more of a detriment to Summoner than a boon. As has been stated by a lot of people, more Spell Speed slowly shifts your Bahamut/Phoenix bursts out of party buff windows. My personal opinion, but avoid melding Spell Speed like the plague.