If the temperature of the heat exchanger raises to a certain degree, the compressor will click on to lower it back down again.
If you have the a\c on max, where the air is blowing really hard, the warm air blowing through heats up the heat exchanger (while cooling the air moving past, thus the name heat exchanger [a radiator]), causing your compressor to click on more often. Max AC setting may cause the compressor to lower the heat exchanger's normal cooling temperature even lower, to cool the air further - Max AC :P
So technically, Yah, it does reduce the ammount of time the compressor is on.
All basic CC is, is a thermameter+computer inside the cab, it detects when it needs to blow cold air, or hot air in the cab and does so accordingly to the temperature you want.