Wall stagger oddities

This cropped up on the gamefaqs messageboard, but I thought I'd repeat it here in the hopes of getting an explanation.

Certain moves which cause stomach crumple on a MC can also cause stomach crumple after a wall stagger. E.g. With Lau, d/f+K into the wall to stagger, f+P+K now causes crumple. With Wolf P+K into the wall to stagger, f+P now causes crumple.

But this doesn't work for most moves. E.g. If Aoi does b, d/f+P on a wall staggered opponent, the opponent is floated for some reason.

Can someone explain why this happens? Why do some moves cause crumple and others not? Can moves which require an MC to execute (like Aoi's D, d/F+P, b+P+G hit throw) be used on wall staggered opponents?

 

Just a note - these were tested in the PS2 version.

 

lau's f+P+K crumples on MC but I dunno why it would crumple during a wall stagger, unless hits during wall stagger are considered interrupts.
Wolf's f+P crumples anytime the opponent is stumbling/staggering.. like after several of his forced-stagger moves.

 

Wall Stagger

Here's the thread /versus/images/icons/smile.gif

 

seems like an interesting query, but if i'm not mistaken lau & wolf's crumple moves on a wall stagger are easily struggled & blocked anyhow i'm 80 - 85% sure of this. why would you be concerned of such an unreliable technique?