I think good pistol shooters easily tradition to shooting a carbine well. The opposite is not necessarily true.
Something I have started noticing is that USPSA shooters that have exclusively been shooting PCC for an extended period, in many cases, are losing their pistol skills. Watching them come back to the pistol, or try to come back, quit, and go back to the carbine, is ugly. Carbines teach eye speed, but the heavy weight, light light triggers, minimal recoil and multiple points of contact of the PCC is very different than shooting a handgun.