Re: How many people are playing on guitars that aren't setup properly?
I learned how to do basic setup work back in the '70s. I was trying to make a living playing music, and had bad experiences with a couple of luthiers who did terrible work, so I learned how to do some of the basic stuff. Saved myself a lot of money over the years.
One thing I learned from Dan Erlewine's books is that setting the radius of the bridge saddles to match the radius of the fingerboard is crucial to playability. Ninety-nine percent of Gibsons need to have some filing of the bridge saddles. Once I started doing this, I went through every one of my guitars with a radius gauge I'd bought from Stew-Mac and was totally amazed at the difference. It literally turned some guitars from so-so, to top-tier favorites. My G&Ls were setup properly from the factory, but several had either been mis-adjusted by previous owners or simply fallen out of spec. But the Gibsons benefited the most from just a little bit of filing the saddles.
And filing the nut properly is huge. It can making tuning so much easier if the slots are cut smoothly. And you need the proper string height if you want to avoid buzzes and still have your guitar intonate correctly with first position chords.
So, you have to understand your playing style and learn how your guitar should be set up for your technique. And with a few basic skills, a dead-accurate tuner and some simple tools you can have your guitars playing "like buttah." Knowledge is a powerful thing.
Bill