To claim, ATC can see anything you select on the flight control panel, be it Speed, rateofclimb or selected Altitude, is complete nonsense...
They see the following: Your Groundspeed as calculated by the Radar (it is not transmitted), your present Altitude (transmitted by the transponder), your Squawk (usually computerchanged to your callsign), and on mode S they actually do recieve the call sign.
Nothing selected ever gets transmitted, and pilots trying to fly faster than 250 below 100 by selecting V/S don't have the slightest clue.
If I want to fly faster, I just ask, or see if I am in class C airspace, where no speed limit apllies...
Nic