I'm tall and lift weights, I'm built more like a football player than a road cyclist, I'm heavy by our standards. I cooked my hydraulic fluid descending Loup Loup Pass on a series of gravel roads with some nasty washboarding. It's hot and dry over there. This was with SRAM stuff, 160 mm.

I changed to Shimano IceTech rotors, the best available. My current bike takes 140 mm rotors, which is a step backwards. Much, much better. I've descended a different, steeper route down the Loup without problems. And many other passes too. But the rotors aren't the only difference; there are cooling fins in the brakes themselves on the new bike, and it's CentetLock which also helps some with heat dissipation.

I don't think the $100 Ice Tech rotors are available for 6 bolt. But less expensive versions are. And all the questionable sounding stuff does seem to make a difference.