A minimum in-flight weight I can understand (many models of the B707 had this restriction) but exactly how could a minimum ZFW affect Vmc?
You gotta have fuel for Vmc to be of any consideration.
Now, on all aircraft that I have flown (transport and otherwise), there has been no mention of any sort of a minimum ZFW, nor is one necessary, so far as I can see...unless you leave bits behind.
