Every neck is going to play better when setup with appropriate relief for not only the neck itself but for the players style of playing
"Straighter" does not mean "better"
When you pluck a string, it's going to oscillate on it's axis - if it doesn't have sufficient clearance to oscillate without touching the frets - there will be a deadening effect with attendant loss of sustain
If you are a heavy-handed player and strum hard - you are going to benefit from added relief
If you have a softer, gentler string attack you can get away with less relief and not encounter that deadening effect
It's really science and more specifically physics that determine your ideal amount of relief for any particular guitar and player
The obsession with setting up for the lowest possible string height is what accounts for a lot of dead sounding guitars
I usually play with a somewhat restrained string attack, but on some solos I really dig in and let it rip - so I set up with a little more relief than I usually need so my solos ring out clearly
I would advise players to experiment with their relief setting and let their ears guide them to the best setting for their individual guitar and playing style - keep in mind that less is not always better
Neck and fret condition is a very big factor when setting relief - it's pretty easy to envision that the closer a neck is to having a perfect fret job, the less relief is required, because there aren't any errant frets sticking up above that perfect plane for the string to hit and deaden itself as it oscillates around its axis
Simply eyeballing the relief isn't a very accurate method of setting relief, because the difference between so-so relief and optimum relief is often only a few thousandths of an inch
An accurate straight-edge and a set of feeler gauges is the best way to reliably set relief
edit - With my guitars, where I've built the neck and done the fret job, my relief setting usually runs about 5 or 6 thousandths - that's a little lower than most factory recommendations, but my fret jobs are better than most factory fret jobs
5 or 6 thousandths works very well for my playing style and my strings ring out nice and clear and I get very good sustain - that is always my goal when doing a setup
5 or 6 thousandths is a relatively small amount - the only way I can reliably and consistently measure small amounts like that is with a good straight-edge and feeler gauges
When you are setting your relief on your guitar, try to approach it without pre-conceived ideas about what is "best" - instead, let your ears guide you to the best setting, and then measure it - you might be surprised by what learn when using this method
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