Chuck, if he has recorded his Gretsch acoustic drums live, it could sound very odd if he adds clean drum VST fills in between, couldn't it?
OTOH, I haven't used SD much, so I don't have good picture of the different sounds, and I'ver never tried "masqueing" VST drums to sit in a live drum track. Maybe it's not as hard as I think?
OR...maybe OP
wants them to sound different to sit on top of the live track.
I did not understand the post so, that the OP doesn't know how to use SD.