could you hook up both ur original xbox dvd drive and a pioneer dvd drive? Like setting one to master and the other to slave...is this possible

and what would be the advantage's of that....?

Yeah there would be no reason to do that because the xbox wouldnt be able to assign the xbox a drive letter and wouldnt ever know what to do with it... Unless u modded the bios to do this but i have no idea if thats possible or not.

Maybe he wanted the other drive to play all media for backups while keeping his original drive for originals?

I just hope we can someday put some firmware on a pc dvd and swap the shitty dvd out of the xbox. So we can play originals and copies on whatever media we want.