I like to see people branching off into other areas of new product development and see it as a definate plus. Segregating yourself into one area is limiting at best and can create walls in the process at worst.
You are an ME that wants to get into design. Great.
You are ID and want to get into the research. Great.
You are a researcher that wants to get into manufacturing. OK, that is a stretch, but if you have mastered the ID and ME before the leap into manufacturing, go for it.
My point is that there is a lot that goes into the NPD process and I find it boring to be stuck in one place.