I've considered that but haven't. If you want to be safe and know a local framebuilder, you could pay to have it done by someone with a jig and experience. I paid a framebuilder to straighten a steel fork, and he only charged me $40. You can just manually pull the frame wider every time you put in the hub, but it will always spring back to its original size unless you really cold set the tubes.
Oil is good, grease is better.
2007 Peter Mooney w/S&S couplers/Terry Butterfly
1993 Bridgestone MB-3/Avocet O2 Air 40W
1980 Columbus Frame with 1970 Campy parts
1954 Raleigh 3-speed/Brooks B72