Thanks for the feedback and information, everyone.
Getting the synthroid dosage right is one of the things I am worried about after thyroid removal surgery. I have great confidence in the endocronologist I am seeing, but I am told here and from others that this can be a tricky thing to get the dosage right.
I was also told two things by my surgeon this morning: they will put me on synthroid immediately after surgery, and the decision on whether I have to take the radioactive isotope will not be made until after the surgery. If I need radiation, I will go off synthroid for about a week before being irradiated. My surgeon told me that the decision to irradiate or not is largely determined by two factors: (1) size of the tumor, and (2) age of the patient. In my case, he told me I am "right on the cusp" of being a radiation candidate, due to having a small tumor (1.1 cm) and my age (52, which isn't terribly old, but on the other hand I am no spring chicken either). Final decision on radiation will be made after they cut me open and get a peek at what is inside. He sounded like he was leaning towards giving me a lower dose of radiation.
I was also told that since I live alone, no need to move out for the period of the radiation. In the UK they put you in isolation in a hospital room. Here they discharge patients and tell them not to come in contact with others especially pregnant women and children. People I have spoken to who had thyroidectomy and radiation checked into hotels if they lived with other people, because the radiation leaves your body through your urine and the toilet becomes radioactive to others in the household. In my case I live alone, so my surgeon said it is okay to stay in my condo if I have radiation. But will probably be a good idea to flush 2 or 3 or 4 times.