There seems to be a bit of a dichotomy here.
The thread started as "learning to play by ear", but seems to have got mired between playing and learning.

Just so, GUEST. That is a point I raised in my first post. I don't know what "playing by ear" means. If it means playing from memory, I have yet to see any clear evidence that it makes any difference how you learnt it in the first place. Steve claims he can tell but seems reluctant to explain how.