This is giving me some good things to look into, thanks.

I do know that hand stuff has effects, and even hand stuff you can't see has effect. But I don't do anything but grip and open/close, I can't hear anything else. I don't know--somehow these musician discussions of what you can and can't do one way or another always sound like someone's selling something. Tired of having to do that palm-muted bass line? you could get another guitar player to do it for you! And that's not all! They're much better than you! Now what would you expect to pay?

   I have to agree, Martin G, usually racked harmonica is too noisy and littered for me. There's something about it that defeats better judgement, like how a painter can't seem to use an airbrush without starting to do "airbrush art." People tend to get carried away, and me too. It's the only thing I've ever picked up fairly easily. Any sane person would've given up my other efforts for lack of aptitude.

I'm not sure what 3rd position is. For some minor things I like a C harp for Dm, whatever you'd call that. For C in Am, sometimes I dive-bend to the missing 6th in the low end, but it depends on the tune I guess.