I am currently applying to D.O. derm residencies. I have several good letters of recommendation. Two from derm dept chairs. The problem, as one attending pointed out, is that there may be a political problem with sending these two letters to other derm programs. Has anyone found this to be true? Do I need to consider only sending my other letters (research, IM) instead of the ones from the dept chairs?

Any advice would be appreciated.

Catering to possible political whims of more or less unknown PD's is virtually impossible, and, more importantly, a complete waste of time.
Know of a person who trained at a brilliant, but highly controversial, dermatologist, and sent a rec. (post residency) to the chairman's arch-nemesis. However, both respected each other, despite academic battles, and all ended well.
If you have good letters, send them.