Negative, sir. Entire optical drive is removed. Same with the GDEMU (the good sd-card replacement for the Dreamcast, which I also have). I would also prefer to have it both ways and be able to use the original games too, but I understand how it's not entirely possible on old systems that don't have HDDs. They tried with the old, serial port attaching SD reader for the DC, but that one kinda sucked (I have it too). At least with the GDEMU it was a plug-and-play, so if I want to (and ever get rid of my 2nd one) I can just plug the GDROM back in.
But for now, I have a spare FZ-1 and a secondary Dreamcast to play original games if I want to. I figure eventually I'll stop caring (though I'll keep my original games because I'm a crazy collector)