Check out the size of the fighting game sprites on SNES. . . .

[Tanooki]

Yeah no doubt.  I'm not, and you're saying as much you're not sure either.  It is amusing to compare.  Roughly, I got SFA2 and my first original (CIB wish I kept all those) SFC copy of Gundam Wing I got around the same time 1997~ and both do the big sprite action pretty well, but they do it in different ways as you said.  SFA2 is kind of the more sloppy approach as such using the SDD1 chip to save on some space to leave more room for the game than a stock cart would get stupid expensive on or just run out of space for data.  And then Gundam it's on the top end of stuff, Phantasia aside, and it's a far more fluid game as far as animation frames and pieces of the characters go.

[turboxray]

The demo isn't showing off any special tricks. It's just showing that given the limited 16k (or two 8k divide banks) for sprites in vram, that you could fit Earthquake into them. And secondly, it can fit a single EQ sprite into vblank DMA (with some screen clipping) - by having player 1 on even frame updates 0,2,4,6.. and player 2 on frame updates 1,3,5,7.. and so on. That means updating the frame of animation, not moving it around which can still be at 60fps. I don't think untypical or unexpected of fighting game home port.  I guess a minor 3rd point would be to show that the snes sprite table isn't maxed either as it only uses 51 sprites, but that's expected. It wasn't busting the sprite table limit on the MD example demo either (which this was inspired by).

 

 You can download the demo rom and see, just like the Genesis example.. you've essentially maxed out the sprite line pixel limit for these idle animations. If either of those characters attacked, there wouldn't be enough sprite line bandwidth to show it without other sprites dropping out. This is something neither demo addresses.

 

 PCE can do this as well, and no screen clipping is required (could show all 240 lines). PCE also has the bandwidth to update both Earthquake characters in a single frame (because vram is unrestricted during active screen unlike the snes), which means if you go SGX - you could have four of these characters on screen at the rate of the snes demo. Anyway, snes takes 51 sprites but PCE takes 30 (pce example below):

 

 

Anyway, this just to give things perspective and not a VS post. I don't think the SNES demo is trying to show pushing limits as so much as showing you don't necessarily need double buffering to show two large sprites - if you're smart about it (I think only 11 lines were clipped for the additional bandwidth). If you download the demo, you can look in the debugger with Mesen. And I think in the case were you need an attack animation, you'd want to use a free snes BG layer to help augment the character attack frame for one of the fighters.