You are absolutely correct. There were times last night that I was bogging down the motor on my PorterCable. It's got plenty of RPM's but lacking in the HP/Torque category. Even my polisher needs some Stage 2 attention now.
I found the first time that I got the best results using the Turtle Rubbing Compound when I used a lot of product. Last night, putting on a lot of product just slowed down the rotation to where it couldn't even turn anymore. The polisher is fairly new as well. Surely I haven't wore out the brushes already??? I know that was part of my problem. I am trying to keep enough pressure that my pad rotates about one full rotation per second. Adding any pressure was stopping the rotation dead cold which left me with just the oscillation movement. I'll have to check into it.