Why does it seem like my car runs better when the A/C is on?

[ChicagoGTS]

It's a strange thing, when the A/C is on it feels more responsive and smoother. Any info would be much appreciated.

~Matt~

 

[STUGOTS]

Because if you notice the RPM's go up a hair when you switch on the A/C that just means your idle may be a little low and when you put on the A/C its going back to "where it should be"