probably used by high $$$ race teams that want every ast drop of power. Snce the engines get replaced/rebuilt quite often, the sacrifice is irrelevant, so long as the oil protects and cools for the necessary time.
Might also make good small electric motor lube???
Used to use it 13 years ago in, you guessed it, Formula Ford race engines.
I was after every last little bit of HP and torque, and this stuff delivered. It's lke pouring water, and has an amazing aroma. It was kown to increase engine wear when going from a straight 30 or 20W-50 race oil to it, what I found to work was to dramatically tighten up bearing clearances (cavitation erosion was apparent) and use a very fine bore finish with plateau honing.
Still have 5 littres, never been game to use it in anything else.