Ed, I can only recall of 3 TECHS that moved to Branch manager,
One was an IDIOT when he was on the road and became an "Idiot" with authority after moving up.

Second one was a great TECH, worked roadservice for a long time and then took stab at management, but the "Business" side of this Industry kind of knocked him for a loop and he went back on the road.

Third fellow I know started out in the shop, went on the road for good while and then moved into parts, then went to sales and after a while went to branch manager. Now after a few years He is operating two branches in two states at the same time, From what I hear, he is one Great manager.

Most of my experiance with branch managers in the past has not been good.
some were all right, one of the good ones we had years ago was not a Tech or had any real mechanical skills but he was decent and got along good with everyone but retired for health reasons.