I noticed how Frame Da-I mean Diddy Kong seems to be a tough match up for Pit. He simply outspeeds everything Pit has with no drawbacks. I was wondering if I can get any tips against that stupid monkey.
There is an official matchup thread where everyone posts and discusses each character. You should always post there for help and input just so the information is in one spot. To me though don't think its a bad MU. Once he goes off stage PIT> PITTOO simply to aim your arrow and gimp Diddy. He isn't much faster than P/Dp and disjoints help so that's an advantage. Haven't checked the thread myself but in case they don't have it you can always just lurk the Diddy forums. If u are having trouble with your opponent it is best to learn from those who main him.
Edit: brief look through their matchup thread and it seems Pit is 40:60 in Diddy's favor. I am going to read it more thoroughly. Still I would suggest to take this into the official MU thread just so everything is in one spot. Remember your problems with characters may also be shared with someone else and it is good to help each other out. This helps to keep the thread continuous and fresh.
Edit2:Also if you can get some video footage of you playing a Diddy that would also be really good.
http://smashboards.com/threads/annals-of-the-heavens-the-pits-user-listing-and-video-thread.369812/ I should read through things more but I do believe this thread will let others critique your style and help spot your faults, at least that's how it works for other forums so I'm guessing it should be the same here.