So many people say they hate Xenogears' Tower of Bable section because "I'll try to make this really hard jump, but then I get into a random battle WHILE I'M IN MID AIR IN THE MIDDLE OF THE JUMP and then after the battle I fall straight down."
That is something that literally never happens in Xenogears. Never ever.
Hmm...this is technically true - the game never checks for random encounters while your character is airborne, but the "misconception" is still justified.
The real issue is that the game would trigger a random battle without immediately transitioning to the battle screen - which allows the player to still move the character
and jump. You can actually hear the disc start spinning in the PS1, and the game cuts off ambient sound effects to prepare for the transition.
So what you described does occur in Xenogears - a player triggers the random encounter while on a platform, the PS1 begins loading the battle screen, the player jumps, and then the game transitions to the battle mid-jump.
Still, I always chuckle whenever I hear this. Babel Tower is one of my favorite parts of the game, despite the awful platforming.
Probably because of the music.
EDIT: ACTUALLY, I think you might be right. I just watched a let's play of the area and the majority of the battles occur in fixed locations (I'm shocked they thought it through). I think the green floating pods that you have to jump on result in the behavior that people complain about - you could slide off of it while still triggering the fixed battle, leading to a battle transition mid fall.
Still, this behavior absolutely occurs in other parts of the game, like the cave before the assault on Aveh/Gebler's Sand Fleet.