Transcoding it won’t gain you much. It’s already been crunched to DVC-HD land and whatever cons are associated with that codec are a permanent part of the quicktime files. HCoding to Pro-Res will give you some small advantages when adding filters, etc…. as the compression is better. But frankly it would be a total waste of time. You’re much better off recapturing to Pro Res.
Having said that, DVC-HD is a very quick and stable codec for editing. Unless your director really wants to do “finishing” work while you’re still in edit. Depends on the scope of the project.