Written music is an extremely valuble tool. But it won't do it all for you.

Quite right, Don. Interpretation, feeling, a good ear, knowledge of the genre, etc., are all bring important factors playing and singing. Being able to read SN is a hugely valuable tool. If people don't want to take advantage of it, that's their choice. All I would say is that they're potentially missing out on some unknown goodies by doing so.