Anything that we can do as patients to help out doctor get closer to helping us is great, I think. Too many times we go into a doctors office for answers and walk out with drugs. The key to being truly healthy is to research, experiment and have a close relationship with a good (and I mean good) doctor.
Just because a rash or a severe reaction to a food doesn't occur doesn't mean that you do not have some sort of sensitivity to foods. Years of eating foods that our body doesn't utilize properly can lead to serious health problems if we don't take proactive approach to our diet and health.
Some extra tips to use when attempting an elimination diet.
Try eliminating sugar. We can become very sensitive to it and it can affect everything from our mood, stomach and skin.
Plan ahead for the whole time. Write up menus. Make shopping lists.
Remind yourself that this is only temporary and take it one say at a time.
Good luck and I hope this is helpful for you!