It will only hurt performance on the bottom end, thats when they are closed. They dont open till like 6800 rpm. You will lose a little torque, I cant say if it will even be noticable by the seat of the pants. The problem you run into is the sled going into limp mode. If you can find a way around that then go for it, if thats what you want to do. There is a company that make a delete kit for it and a thing that plugs into your computer so it doesnt go into limp mode. I cant remember who it is, someone on here will.
If you are running a good oil, and you get the cables adjusted properly to start with you really dont have to mess with them. Maybe once a year clean them out, take a total of 10 minutes.