"Oh, twins." That makes more sense, then. "I dunno what's off-- what I put in it shouldn't matter, so it's gotta be somethin' either in the conversion process or the power relays. Or maybe the horse kicked it or somethin'."

It's not that Thrust is unintelligent-- far from it-- so much as that he hasn't had a lot of room or time to really sit and make this work. (He could have done, but once he was sure it was running, he didn't stop to test it. Being hungry or the equivalent and wanting to keep moving wasn't really conducive to beta-testing.)