I've watched all of my recorded matches at least 15+ times each. I find it so much easier to learn from my own videos because I don't have to guess what the player is doing. Like I might watch PP using a certain move in a certain situation, but I have to kind of guess what he was going for, what he was predicting the opponent to do, what kind of DI he was anticipating, etc. When I watch myself, I can easily figure out stuff like, "Oh, okay, I kept dairing them even when they DI'd in repeatedly. I should have started nairing to continue the combo."
It's also PERFECT for analyzing your defensive play. It's often pretty hard to improve on your defensive play because you can't practice it on command. If I want to work on a certain type of combo, I can just do it as often as possible and when I lead into it I can focus on it. If I'm getting rushed down by a Fox with a bunch of different approaching tools, it's hard to tell where exactly I messed up because I wasn't focused on avoiding any one approach. I'm trying to avoid a bunch of stuff so I can't just focus and practice avoiding one thing because I will just get destroyed by everything else. It's usually just reactionary stuff, and by the time you're knocked off stage and are trying to recover, you have a hard time realizing what even LED to that situation, let alone how you could have improved. I think this is an especially huge deal for me because I get such limited practice vs. most characters that I fall for a lot of gimmicky stuff that I haven't been exposed to before. If you've never been drop zoned by a Falcon or LH faired by a Sheik, then obviously you are going to fall for that **** ALL the time because you haven't developed a reflex for it. Those two examples are pretty obvious in-game, but the more subtle something is, the harder it is to identify on the fly.