Thanks everyone for your throughful responses. Especially Bill M – your video has genuinely changed my perspective.

A couple of things you've all helped me learn:

a) Starting-out doing G Major with the little finger makes no sense. A video series on another website is teaching this. With your help, I now realise this isn't conventional for beginners. I'm happy to report that my hand is phyically able to make a G Major with fingers 1, 2, 3.

b) I should do Lisa's Fundamentals course

c) There's more than one way of doing things. This is probably obvious to experienced guitarists, but it's not obvious starting out. Bill's video helped illustate this – thank you.

Thanks all. On with the practice...