Anne, you are right you don't *need* them. But you know what - your healing may be a lot faster with them than without. The only way to know for sure is to try it and see.
Even the full thyroid panel (and some of the new fancy tests) all have problems. One of the biggest problems is that many people with candida tend to have "normal" looking tests, yet have many/all have the symptoms of hypothyroidism.
Personally I think the basal temp test is the most reliable.
I think hypothyroidism and hypoandrenalism play a *heavy* part in CFS. These are the first 2 things I would check in someone reporting persistant fatigue. Only then would I look for other causes.