Not sure I agree with you, BPF. There are several training benefits of going right down to actual Vmc which I can think of. Safety is, of course, paramount, and your story of the snap roll is sobering, but - my personal opinion, I have no problem if you don't agree - there is no safety issue demonstrating Vmc when I have control of the elevators, ailerons and throttles.
Other instructors may do this slightly differently, but here's how I do it:
QED!
(I started typing up the benefits of my method, but then stopped because I feel this conversation really belongs in the Instructors forum rather than Private Flying - it relates solely to instructing technique. If you're interested enough to continue discussing, let's start a new thread in there.)
As for your snap roll, I'll bet you were glad you were at 4000' and not 400'! Makes me wonder how I'd handle that... I haven't done any aeros other than spins for nearly 10 years.
FFF
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