If that's happening you should try learning them by tracking something about them visually. I can do all my algs one move at a time throwing the cube up in the air and catching it between moves, because I learned them by seeing how f2l pairs or something else is moved around. I can do them backwards like that too. Muscle memory is of course important for speed and having a clear mind to think about what's coming next, but you should be associating that muscle memory with something more knowledge/visual based. You then not only remember it longer, but you don't make mistakes as often either. Also, when you do make the inevitable mistake, you notice immediately and can correct it easily. See my previous post at the bottom of page 18. If you learn what I explained there, you can use it forward (Gb), backward (Ga), mirrored forward (Gd), and mirrored backward (Gc) for all of the G perms.
