Yamaha DTXpress/DTXplorer/DTXtreme

I talked with a Yamaha tech about my recording problems, and he said that 
the DTXpress isn't made to record two different drum sets at the same time.
Not good in my opinion.  Anyway, he affirmed my suspicions, and maybe
every one already knows this, but the DTXpress doesn't actually store any 
song information after recording.  It only stores information that commands 
the triggers to function (a little memory saving trick).  So, when you play back a recorded song you aren't actually playing the song, you're playing back info that tells the triggers to work in a certain pattern.  This would explain the inability to hear track one as actually recorded while recording track two if the drum sets chosen for each track are different.  Anyone know any ways around this?  If not, I would say this qualifies as a major design flaw.  It basically defeats the purpose of having a two track recorder in the first place.