it does, but I'd still recommend Air Sup as it gives you a good element of soft control over your target, after all, they can't attack while lying down. it works well against paragon protectors for example, just to stop them from elude'ing or starting up unstoppable.
Defiant 50's
Many and varied!
@Miss Chief
Air supe with BS works rather nicely. my BS/Invuln has air supe, and the enemy is just getting up when he takes the sword to the top of his skull. I imagine it'd stack nicely with Headsplitter at 32, which also does knockdown. Air supe --> Headsplitter --> Disembowel, should all combine to make sure your target is KO'd without ever getting back onto his feet.
Does having air superiority with katana/broardsword slow your chain down, being as you have to put weapon away to use it?