Katie

Back to your medical issues. sorry I let myself be taunted into being complicit with that hijack. It won't happen again. Consider asking for a copy of your pathology report. At a minimum, ask your oncologist if the pathology report shows any indication of PNI (perineural invasion/involvement) as that is a bad sign.
As to the selective neck dissection, you could also ask for a PET/CT scan first. While Petscans are very inaccurate for mouth and tongue tumors, they seem to be very accurate for lymph nodes. I have had a selective neck dissection, and my surgeon was very careful not to damage or cut the muscles and nerves in the way, but even moving them out of the way to take out the lymph nodes causes trauma. There are serious consequences of a neck dissection in terms of shoulder movement, and ability to raise your head and your neck skin turning almost fossilized. Lymphoma and swelling are issues also, plus the lymph nodes are not like your appendix, they actual serve an important function in your body.
Worse in my mind is that many many times all of the lymph nodes taken out turn out to be cancer free, and while some posters are all excited about that, it means that this was an unnecessary surgery.
Of course you have to trust your doctor but wouldn't you feel better if your doctor addressed all those concerns with you rather than just doing a neck dissection "just in case".?
I got a lot of flack by refusing a neck dissection for my first cancer, but when I had to have the salvage surgery to take out the tumor after the recurrence, the same nerves and muscles and area had to be traumatized so it made sense to get the neck dissection done. It turns out that not one of my lymph nodes did have cancer which validated my first choice of being cautious.
Oh, and one last piece of advice, since you have not had and may not even need radiation, it's the perfect time to ask for a blood test of your TSH level, the thryoid hormone. Unless you know your exact TSH number now, before radiation or chemo, you may never be able to fully recover since the lab tests for TSH levels are so wide in range that they are meaningless for an individual. The best guidelines suggest doctors do this, but most ignore it. But it's very very important to know since after TX, you will want your TSH level to be the same as before.
Charm