The maximum update rate for the controller when using the VEXnet radio is 50mS, that is, you can ask the controller to clearScreen* or print a line of text every 50mS. So remove clearScreen from the loop and just use the print command. To clear remaining text on an individual line, just add some extra whitespace like this.
ctr.Screen.print("rpm %d ", value);
- with 1.0.1 or later, 1.0.0 took longer for clearScreen.