Hmmm, maybe a little balance needed here....
As an ex-CTCer, I don't recall completing an asymmetric cct in the DA42 where the "dead" engine power lever wasn't advanced to the point that the gear warning stopped operating (simulated feathered setting) once the dead engine had been simulated switched off; the usual pratice was for the instructor to do this so as to avoid the obvious trap that seems to have been assumed in the above posts. (It's also pretty irritating to listen to so why wouldn't you cancel it as soon as is sensible?). Admittedly this was a couple of years ago but I'd be surprised if the procedure has changed.
Clearly, someone's dropped what we assume to be a perfectly servicable aeroplane on the runway with the gear up, but it seems a little premature to make a whole series of sweeping statements about the quality of CTC's training / procedures based on very little fact.
Just my 2 cents worth.....