Got invited to join a band... but I'm a hack.

I would like to add that music is subjective. Some of the best songs are written with only a simple bass line, and with 3 chord structure. Do not ever let anyone tell you differently. People that think otherwise are only fooling themselves that flashy is more better and gets people places; it does not. As long as you remember golden rule, of HAVING FUN with your craft and the people who are in your band, that is all that matters. I think that you'll be great! Keep up the good work. Don't worry much about theory. Most bands do not know anything about such. It is good to know, sure, but being a mechanical player isn't always the best thing! I am a mechanical player, know how things work and constantly want to learn about theory and the like; but I lack being a “feeler.” Feelers play like a magic show; with feeling, never knowing what they are playing and just go with the flow. No one way is the wrong way. Most people will lean towards one or the other. If you'd like, I can send you some links of my personal bass teacher who is bar none and very encouraging. I've been studying with him for about 3 years now. The best teacher I have ever had. He has some things on YouTube that could help aid you in your journey to wanting to know about theory a bit more.
How are you doing so far? I'd like to know about your progress.

I might be wrong, man, but, I believe the “5th fret” reference is from a Chet Atkins quote. But, like I said, I may be wrong. I wouldn't worry too much about the “theory” part. It's OK to know all about it, but, when it gets down to putting notes, chords and melodies to your lyrics, I personally don't see where “theory” plays that big a role. Like someone said before, if you don't “feel” what you're writing about, then it's probably not gonna make very much sense to the listener or anyone trying to cover your song. I write on the piano/keyboard, then work out the Bass to go along with it. In some people's eyes, I may be doing it wrong, but, it works for me. God bless and have a great day. Gene Bellamy