Haha. It's recently gotten worse at nearly 3yo, because he's much stronger and thinks playing with poo is funny. I've mastered the art of several wrestling holds, could probably go pro.
Unfortunately I don't think this knowledge is transferable! I recently changed a friend's toddler, and nothing worked. She was a kicker, where my son tends to twist his legs around to gain leverage and flip over. I think it's all stuff you figure out by trial, error, error, and more error.