Is this common? Looked down upon?
In particular, I'm thinking about attending a school in the NYC region that is very strong in logic but perhaps not quite as strong in another area that interests me. I'm curious if -- down the line -- it could be a realistic option for me to try to get an adviser at another school in the disaster scenario that I don't want to do a dissertation in logic.
This would be something closer to a disaster scenario, and not a plan of mine going in, but I just wanted to make sure I know what I'm getting myself into beforehand.
PS -- It is assumed that X does not equal Y in the title