Hi Corbin,

For what it's worth, your circuit is very similar to what's inside an Omni regulator. The Omni regulator uses a larger transistor on the output stage (rated for 10A, probably a bit overkill), as well as a flyback diode (about equivalent to a 1N4002). It also uses a 6.2V Zener after running the voltage through a divider, instead of just a 14.xV Zener. Functionally, the two circuits are nearly identical, so I bet this trick would work using the Omni regulator as well.