That Dayton shop story is a good point, but leoshah is right about paying for the whole machine. The thing is, 95% load on the gauge isn't always 95% real stress. If his cuts were smooth and the tool was good, the spindle bearings saw clean force. A bad setup at 70% with chatter is way harder on everything. It's more about watching the whole cut, not just the number.

You're right about it feeling like a gimmick at first, @skyler_anderson65. I held off for years thinking I could just guess. The real change for me was testing my oven's actual temperature. Found out it runs almost 25 degrees hot, which explained a lot of my baking fails. Now I check everything, especially pork chops, to get them just right.

Heard some folks use burner phones for that now.

Ouch, @umabailey, but at least you learned, right?