Lol, so much flaming going on. I'm sorry, from now on I'll keep my advice to myself. Just play some TL's online, you'll notice that many of them DO spam the d-air.
And lol @ the comment saying I just hate D-air. Keep spamming it, I really don't mind, I'll just win as Peach, a low tier character who is countered by your top tier character. Makes me laugh, knowing that I *should* be losing.
And yes, the D-air does suck. It has 2 situations, on and off the map. On the map, F-air or B-air will always be better, as they do similar damage, with better knockback for comboing, and the ability to follow it up. Off the map, you can spike, but a good opponent will air dodge and get you both killed, because they'll know that if they get spiked they lose anyways. Maybe if it could sweet spot the edge it'd be nice, but otherwise, there are better options for almost any situation.
For eating shields, you can grab. For comboing, it's lol. For recovering from mid-air, well, TL's aerial game is so incredible that you should rejoice when the fight is in the air. For punishing, you can't follow up on it. And for spiking, there is a very large chance that you will die from it as well.
If *YOU* don't spam the d-air, then you have no reason to read and reply to my thread. It's like you take offense to the fact that I'm pointing out what many of your character's players do. If you don't, then what I say doesn't apply to you, so you should feel good about yourself knowing that your game has evolved beyond that point. Many people's games haven't. There's no need to flame me for offering some constructive criticism.