>I actually like for people to show me up. It gives me a direction and how I should improve my playing to match and exceed their level.

Me too, it's a great way to improve as a musician, and so far as technique it has really helped! (it's like programming =) Maybe as time comes on I'll have time to pick apart composition later too.

>Sometimes playing notes that aren't on the page is a good thing!

Actually, on the contrary I am from a rather different school of thought in the sense that though I have studied theory, I am focusing more on the melody and riffs while recording. In fact I usually just solo freely and pick whichever melodies sounded nice for a recurring theme later on (thanks to keen sequencing software!) But there are a few that I've actually taken time to write as they fit the groove and they end up to be in my opinion my best work.

At any rate, music is for me, but I am interested of any of you have any keen references for songwriting so far as structure goes that you might know of!

>Their whole purpose is to invoke emotional responses in the listener (and it does). Is that a little less vague?

Hm, reminds me of Indian Raga at that. Yes that is less vague, thank you very much Thantos! =)