Not really. Kap was a unicorn athletic qb who worked best in a quick strike passing game and improvising on the move out of the pistol. Harbrau and Roman tried to make him read defenses from the pocket and run as a last resort...which he still had to do a lot because his OL's deteriorated each year and he had old, slow receivers. Look at his stats, he never improved from his first year, year and a half when he was still a novelty. He didn't show any meaningful progression as a passer until, oddly enough, Chip Kelly and Ryan Day got their hands on him.
Harbrau does deserve credit for recognizing Kap's unique skillset and turning to and sticking with him when Alex Smith got hurt in 2012, but I'd hardly say he showed much development under the harbrau regime. In fact, he was hard broken by the time harbrau got the boot.