I agree about practicing. I'm 47, and one of the good things about starting something so complex now is that I don't have to learn how I learn. I've been doing the same thing. Instead of practicing for 30 minutes, for instance, I've been practicing for 10 minutes 2-3x a day. That way it makes me want to go back and pick it up again.
Also, even though guitar is new to me, I think I have a better sense (at my age) or when I'm "doing something wrong" or when it's just a fact of inexperience, if that makes sense. In this case, I thought there was something that I didn't KNOW that I should be doing...
Quickly advancing from inept to semi-ept