[steadyryan]

I recently started working with a great tech, and he's showing me everything, and that situation has come up a bunch. He says he always covers it. He says he's tried both, but hasn't found a noticable difference in sound. He does say that by corking all the way to the edge, it helps (slightly, admittidly) with the seal and sturdyness between the mouthpiece and neck cork. So, there ya go...