Sorry, my point was just that when you lower the stop-bar you increase string tension. Your neck will move forward so the "sounding" part of the string will be shorter and not intonate well. When you bring the neck back to your favourite, some, at times most of that will go away but to get it right, you still have to listen and adjust... I think, it ll comes down to the neck boring more or LEDs stressed. If anyone's got another idea, I be glad to hear of it.
Do you care to explain how a neck can move forward. Are we taling about a Gibson like tail piece / bridge configuration or a Fender like trem ? Sorry, but you lost me there.
Tension on a 42 gauge string tuned to E on a 24.75" scale guitar will be X. Tension on a 42 gauge string tuned to E on a 24.75" scale guitar with a decked tailpiece will still be X. Tension on a 42 gauge string tuned to E on a 24.75" scale guitar with a raised tailpiece will still be X. Read this: https://www.stringsdirect.co.uk/blog/string-tension-101/ Nowhere is there mention of anything that happens outside the scale lenght, because it doesn't affect anything but the arguing on internet forums.
"Borderline sharp fretted 12th?" In my experience (56 years), when playing publicly, there isn't a soul in your audience that will come up to you during a break to tell you that your low E string is out of intonation. They either won't hear it, or are too stoned to hear it, or care, if they can. In the case of a guy with perfect pitch, tell him to fu... buzz off. It's easier to hear when you're playing alone. In a band, you're agonizing over nothing.
You're absolutely right of course. The same goes for agonising over tone. But some of the time you are playing alone and then you notice every problem. You need to be able to put it right for those occasions.
Should've said the neck "bends forward". Due to increased forward stress. I wanted to say that when I increase spring tension on my Strat I found the same phenomenon: String tension, allthough very slightly, increases and I have to readjust neck relief, if ever so slightly. But, as most of us will have experienced, with guitar setup, a little bit goes a long way.