Azen is pretty much good to amazing with just about every character in the game. Its not surprising that his playstyles may carry over from certain characters to others. Plus if you watch other videos of azen's falco he doesn't f smash like that
http://www.youtube.com/watch?v=RW-sGTvn-Zs for instance.... I think maybe he was doing it just because its a bit unorthodox and he figured he could get away with it a few times. Either way he doesn't play falco for the majority of his tournament matchups but he's definitely comfortable with him he just plays a more conservative falco that uses pretty much the basics that falco needs to win: SHL shine combos and shffling, but since he has solide mindgames and a good feel for the game he knows how to put them to good use.
I know my technical skill with falco is probably better than azen's (obviously I can't know this for sure but from what he demonstrates/uses in the videos I've seen I'm just assuming he isn't comfortable LHDLing and JC shining with falco enough to use them frequently) yet I'm pretty **** sure if he dittod me with falco I would get my *** handed to me on a silver platter.
I think sometimes we forget that one's skills in smash with one character can often carry over. I know I do whenever I see a pro bust out a character that he/she doesn't use often....... and then I'm like wtf HE'S AMAZING WITH (random character)... like when Azen used captain falcon against chudat in MLG one of the commentators was like "why is azen using captain falcon?" and husband responded "why? because he's amazing with captain falcon!"