great question !
I like my guitar tone set so I can ping the pinch harmonics out as and when I feel the need also.
I've never fully understood what the difference is between different setups either.
I can remember years ago I was relatively happy with my tone, until I saw some guy playing on YouTube absolutely ringing pitched harmonics like bell with a rocktron prophesy.
I went on eBay within the week and with a bit of tweaking there they were. I'd been convinced for years my technique was crap!?
I definitely think as the others have said it is a combination of everything ...... the point someone made about volume was interesting.... I will try that later.
I personally think alot of it is the guitar itself. The pickups and amp settings and all the rest either bring them out further or squash them.
I'm only very much a hobby player, but have a few different guitars. I don't tend to change the pick ups, just keep the stock ones. Some guitars ring really well and some you can't get to ring very well at all even in the same setup.
I bought a washburn st3 years ago, loved the shape and feel but couldn't get the pinch harmonics ringing very Well, even after pick up swaps, so sold it.
What I find odd is I've got an Ibanez with a tone zone and an air Norton in neck which is my easiest guitar for me to hit them and they jump out right out. Even in the neck !
On the flip side of that.... I've just bought a Bernie rico Jekyll with bare knuckles in it and I've got to really work hard and tweak some setting to bring them out.
I love the guitar, but if new pickups and a thorough setup doesn't help, that guitar will be sold too.
As an experiment, if you've got pro