Much of the 'Basic Service' RT traffic can actually hinder the LARS ATCO from executing his primary tasks by preventing him from using his primary tool. Similarly continuous chatter can actually prevent someone from saying something which actually happens to be important. Think 'is your transmission really necessary'.
This sums it up brilliantly. If only the CAA would put this in their guidance in very big letters, and all FIs would teach students along the same lines.