Elf / Jo'ou: Yeah, Zegai is trashy in Middle, no arguments there. Although I'll add that I don't feel so bad about Wrath anymore because double-checking the stat topic it just says "50% healing." Ah well. That said... for the Zegai vs. an average training dummy (DW1 Hero sans-spells?), and assuming S5 DEF/MDEF is subtractive as suggested later on in the stat topic...
Average PDEF, MDEF, HP: 236, 229, 480
Zegai: 282, 177, 598
So if we assume it's pure subtraction, Zegai shaves .10 PCHP off every physical, and takes an extra .11 PCHP from every magical attack. He's got 1.25 PCHP at base. So average fighter has a high 5HKO of Zegai, while the average non-elemental mage has a high 3HKO. Anyway, maybe this interp of defense is totally wrong, but I agree that Zegai is le bad if he's just barely avoiding physical 3HKOs as Jo'ou says, but avoiding the 4HKO from average helps a lot, and helps even more against some of Light's fighters who can't even muster average damage (but are still okay for other reasons). Anyway, even if Zegai is eating a 3:2 by average (which I don't see), if he's given that durability... Hero/Zegai/Hero/Hero/Zegai/Hero/Wrath/Hero/Hero/Zegai -> Zegai wins despite being at death's door (2 regular hits + a Wrath hit should kill even a moderately tanky fighter). He might even win if he's 4HKOed in such a situation if his opponent is a bit frailer. (Real DW1 Hero probably wins with healing on all the doubling he's getting on this interp, I think.) Then toss in my higher TB speed caps that pretty much only let speedy characters get a 3:2 on Zegai, and Zegai is a pretty sweet slugfester in Light.
Pyro: I'm pretty much with Jo'ou on this one on your evangelism. You've played FE games! What is it you check before moving a character, especially a character with suspect speed, into enemy territory? Whether they get doubled by the enemies that'll be in range to attack, of course, because of the huge and often fatal difference between getting doubled & not getting doubled. Don't get me wrong, the whole doubled percentages thing is neat, but it gives up this extremely huge part of in-game FE play, and I can't consider that anything but a flaw. If a character doubles half the enemies, doesn't get doubled by 45%, and is doubled by 5% of them, their offense is not "consistently ~1.5 times a normal attack no matter who they face," it's spiky, and their defense is generally fine except when they run into the occasional speedster.
Now, the reason to go ahead and use it anyway is "blargh I can't find anything in the DL that corresponds to FE AS" and not wanting to assume that all DL enemies are average AS, which leads to the giant split of doom between "faster than +3.5 AS" and "not." So yeah, I respect the view, but I can't really see it as a hypable "FE's perfect translation to the DL with no more issues." It's a different translation to the DL is all that gives up a rather key feature to in-game battles. (It should be noted that if Zegai was a FE character, I have very little difficulty believing he'd be the General type, since he fits most of it already - low evade/parry, high DEF, lowish MDEF, low number of attacks, while someone like S5 Richard is clearly a Myrmidon with a high number of attacks, just like FE Myrmidons. So you can make a holistic argument that even if you use doubled rates for unknown AS DL enemies, you can take a good guess from S5 number-of-attacks, at least for the fighters.)