I've been playing 22 years now, and it still happens to me. I forgot a song totally last night that I play live more or less every week - once I jogged my memory with mp3 it started coming back, but the mental blocks are still there. I have good days and bad days... It's all just repetition, so as long as you keep cramming it in there, most of it won't fall out!

And I reckon Satch is quite probably the greatest....