It has always been my understanding that in classic Street Fighter (ie. no focus attacks or extensive damage-scaling) and similar games that cross-up jump-ins (in addition to potentially forcing a defending opponent to guess which direction to block) usually enable an extra hit in combos for more damage.
Example: In Capcom vs SNK 2, Ryu can combo from cross-up j. forward kick into close or crouching fierce and be close enough to finish with a Shoryuken. He'd be too far to do this from a normal jump-in.
In spite of this, I have yet to see a match in which a stunned opponent eats up a cross-up combo. Are there any significant obstacles discouraging it? Is the timing any more strict to cross-up "deep" enough to reliably combo into the next attack on standing opponents (that are stunned), or is it just me?
If I just need more practice, are there any highly-regarded (particularly Ryu) players known to use this tactic? If so, what footage is available of them doing this? Do high-level players choose to forsake the additional damage of a cross-up combo to avoid error in high-pressure situations?
Best Answer
Unless the cross-up combo will lead to additional damage or some other concrete benefit over a normal jump-in combo (which, off the top of my head, should happen rarely, if ever), no, there's no particular reason to do that.
In general, the main benefit of cross-ups is that they force the opponent to block in the opposite direction. Ambiguous cross-ups are useful in that the opponent can't be certain which way to block at all. When the opponent is stunned, they can't block -- period -- so the primary benefit of a cross-up doesn't apply.
There are always exceptions, of course, depending on what game you're playing, what character you're playing, or what character your opponent is playing. There will even be variations based on the length of the combo that led up to the stun, as in many games, the internal damage scaling of a combo doesn't reset when an opponent is stunned, meaning that short-and-sweet combos may lead to more damage post-scaling than longer ones.
As a general rule of thumb, though, my personal experiences have led me to feel that you should focus on the shortest, highest-damage combo you have at your disposal, unless you know for certain that the optimal combo in that situation starts with a cross-up. This sort of thing is typically pretty easy to experiement with in training mode, so feel free to try different possibilities out.