I can. If your engine speed is below 8k speed the pump up.
The only reason to slow the pump down is if you can’t keep the belt on.
At some point the fan, ANY fan will become less effective and will fail.
That’s why you slow a pump down.
For the drive through idle guys and the rest of us not turning that kind of rpm need to speed the pump up.
The fact that this is still being discussed is proof positive old myths never die.