Neighbor does that. It isn't any more convenient than using the combine, in fact it is less so, because you have to look backwards to see if you are going to catch the fencepost or whatever, instead of forward.
What the 3-pt carriers are really good for, is for parking the head in the back of the shed, a tractor is far more maneuverable than a combine, and you can get them in corners better.
For transporting a head, I'd use a head trailer, or to save money, just get the brackets for one, and put them on an old wagon gear. The 3-pt carrier is nice in that you can remove one head off the trailer, set it on the ground, and then unhook the one on the combine onto the trailer, and hook to the other. Saves having to use the combine for so much dallying around.
