Mica,
I'm one of those that didn't have a neck disection, even though I had an advanced tonsil cancer. It was presented to me before treatment started that, in my case, the procedure would not have resulted in any great advantage over just radiation and chemo alone. The H&N surgeon and my team thought my odds were actually slightly better without the surgery. They also said that the surgery would result in fairly major quality of life issues for me. Please note that I had no metastesis or node involvement - that may well have changed the whole treatment strategy. I followed the path that I thought would give me the highest chance of survival. If the neck disection would have improved my odds I would have done it. So far at 20 months post Tx I am cancer free. As you can see from these posts, the jury is pretty evenly devided on whether to have a disection or not - it is a decision you will have to make with the guidance and advice from your medical team.

I don't think anyone addressed your original question - yes it is common to radiate and shrink a tumor prior to surgery.

I would get a second opinion just so you can feel comfortable that the path you are taking will afford you with the highest survival possibilities.