That's not how people increase their mouse sensitivity. Most higher end mice have buttons right on the mouse that control mouse sensitivity, so it can be adjusted on the fly. Other mice have program-able software and people can set up a macro to change the sensitivity on the fly. Hell, anyone can open their control panel and permanently increase their mouse sensitivity with the standard options in Windows.
Also, you just introduced a new exploit for people to try. Bravo...
Finally, THE MOUSE SENSITIVITY "EXPLOIT" DOES NOT RUIN GAMEPLAY!! Hardly anyone abuses it, and the few people that do certainly do not change the tide of a battle. Sure it's annoying when you can't run circles around a KT in your Cromwell, but get the hell over it. These people paid extra money to get a better mouse than you have, which they have all the right in the world to do. Do you want to penalize people with better computers and internet connections because they lag less than you?
For the record, I play with a shitty $20 Logitech mouse, and yes, I do get pissed off when people are obviously abusing their mouse sensitivity, but guess what? I get over it, outsmart the bastard and send him and his tank back to the spawn screen a different way than "Hur hur, I'm gonna charge him in my tank".