lol, I've been playing keyboards since I was 3, 14 years of doing so professionally, and can't read/write music...I have NEVER "picked it up." I can read chord sheets, that's it.
I have a mental block, because to me it's like trying to put mathematical limitations on something that to me isn't mathematical. I'd compare it to trying to put a concept like "beauty" or "courage" in a box...impossible.
One of the reasons I'm curious about Neil is, during the webcast I heard him tell the other musicians what key "Fall At Your Feet" was in. Now, he didn't say "the song is in the key of E-flat," which it is. He said, "it's in C-minor," which was not the KEY it was in but the STARTING CHORD. Something as subtle as that makes me think he plays by ear. And if so, that makes him even more extraordinary in my book!