I was going to type a smart assed reply and say I figured out my fit and position about 30 years ago and stuck with it, but thats really only the case with my road bikes. My most recent road bike, a Topstone, only got a different stem after a few weeks of riding. Its been the same for 2 years now, as have my 2 other road bikes, haven't changed them in 10-20 years. I did initially take off 50mm of bar width on my HT purchased 3-4 years ago, I also last year moved to a slightly longer stem. A new FS had its bar trimmed by 20 mm to 740 and I settled on that width and just changed to a 740 on the HT. So I do tinker on occasion