i usually don't reply to posts, especially those that can be easily answered with the search function. but i'm bored at work and what the hell, i feel like being nice...
what makes this matchup difficult for most IC players, as well as vs marth, is that you must simplify your playing style and simply outplay your opponent. all those fancy ground tactics and bull**** wont work here son. a good peach will gimp you all day and **** your **** up. if ure trying to come on here looking for some easy tactics to beating her, you're out of luck. she's gonna float all day and you're going to have to fight her alot in the air. and as you know, peach's airgame is far superior, making this an uphill battle all f'n day. you know this, your opponent knows this, so good luck partner. in the air, its uairs and bairs all day. they're one of the few things you got going for you. on the ground, mindgame to fsmash. you'll find fsmash much more efficient than dsmash as it hits her even if she floats above you. get a grab? gj noob. infinite. dthrow > fair > dsmash works sometimes. and you also may be able to sneak in a dthrow > dair cg or two. otherwise, it should be dthrow > upsmash ftw. any halfway decent IC knows these basics, which is why the difference between winning and losing comes down to your mindgames. you just gotta step it up. there's no gimping here, this is pistons-lakers circa 04. you gotta earn your win here. or just infinite, which is like winning, only you're a loser at life.