I heard someone - I think it was Bobby, but it's been a few decades now, so no promises on that - say that playing with Phil you spend a lot of time going "What is he doing??" Then you go back and listen to the tape - and then you speed it up, and you realize "Oh, that's it - he is playing a repeating line; it's just 38 bars long."
Also remember Bob & Jer talking about trying to figure out what Phil was, ad when you do "you start to tailgate on that - but he'll hear you do that and change it up." "Yeah; he'll detailgate you".
Peter