And those pro drivers have all the knowedge about radio technology?

Ofcourse, when it works it is fine, that is the standard aswer from most people but mounting a transmitter on top of a receiver is asking for problems. These guys do build a car to perfection and take care of no binding in what ever but stick the transponde in a way which is far from perfection.
Also mounting vertical is asking for problems, it will give a weak counting signal and going to far to the side of the track can cause a missing lap (and I have seen that happen also).