Use Your Cruise Control!

I did a lot of driving on interstate highways during the Christmas and New Year's holidays this year and I just had to rant a little about the way people drive. I just don't understand why people can't maintain a constant speed. Do they not realize that it's important to maintain a constant rate of speed and stay the hell out of my way?

I suppose, ideally, everyone should drive at the speed limit on the interstate highways and maintain that speed, but since that isn't going to happen they should at least stay to the right unless they are passing someone, pass as quickly as they can, and then move back to the right as soon as they can. I am amazed by the number of people who will pull into the passing lane in front of me and then slow down! What are they thinking? Are they insane?

I like to set my cruise control so I don't have to try to maintain speed manually, but I'm constantly having to slow down for people who pull in front of me and then drive along slowly until they decide to get out of my way.

So, if you could, when you are driving on an interstate, for God's sake, decide how fast you would like to go, set your cruise control, and then only move to the left to pass someone who is driving slower than you are.

Thanks!
-Rick