Well.......sorta. In some cases it CAN HELP the overall upper temperature by opening sooner and stopping heating up sooner. It did in the case of my slant 6, but you are overall correct in that in general, the thermostat does not control max temp, but the minimum temp. I also think in my case, that changing to a high flow thermostat helped too. Since I went with the 160 high flow all at once, it's difficult to tell "which" attribute helped. In a good hot engine though, it cannot hurt a thing to run the 160. Just tune for it and you'll be fine.
