I have two subject tests with full scores in both. Is it necessary for me to take a third just for Georgetown? I know Georgetown highly recommends three.
I don't know much about Georgetown, but if it is as you say (that they HIGHLY recommend three subject tests), and you really want to get into that school, I would definitely pay attention to what this school is suggesting you do.
If they're highly recommending that their applicants take three subject tests, you should probably look into taking a third, because that means that they may not be impressed enough with your two.