although many new pilots have been caught out by the fact that often the first thing that happens when you apply full carb heat is
the engine runs worse 
, this is because the engine has to ingest all the water you just melted.
BPF,
Yes, I was one - see my post above:
http://www.pprune.org/private-flying...ml#post8966722
In my opinion, all pilots should have carb icing demonstrated to them, preferably early in their careers. For many, it is just a rote procedure during the run-up and downwind checks, taught to them by instructors who may not fully understand the process and may not be following the POH instructions.