"RPMS" v. "RPM"
Your readers sometimes refer to "RPMS." You recently used the same incorrect term. RPM is the abbreviation for Revolutions Per MINUTE, not Revolutions Per MINUTES. I am surprised that you permit, even encourage this erroneous pluralization to continue.
RAY: We have a Staff Grammarian, I.M. Shirley Wright, who usually corrects us when we make grammatical errors. She's still trying to teach us the difference between "bringing" your car to a mechanic and "taking" your car to a mechanic. I still don't understand that one.
TOM: The term you refer to, RPM, does stand for Revolutions Per Minute. The term we used, RPMS, is an old English variation on RPM. It's a more formal usage which dates back to the nineteenth century. It stands for Revolutions Per Minute, Sir. I would love to discuss this at greater length, John, but I have to get to the bank before it closes so I can cash my CDS.