just after rotation, low speed, high angle of attack, one engine windmilling, one t/o pwr, a.s.o., give me an example where there is actual a worse case?
Quite gladly. Two, in fact (since Englishal's post got me thinking about one that had escaped my notice!)
1) As per your example, but with a different amount of flap selected. (In the case of the Duchess or the Seneca, I don't know whether selecting a small amount of flap would, indeed, increase Vmc, but you said yourself that it would and I agree that it might).
2) As per your example, but at a sea-level airfield, on a colder-than-ISA day, and with high pressure. In these conditions, the good engine will develop more power and more thrust than it would in ISA conditions, hence more asymmetry (thanks, Englishal!).
Both of these are realistic scenarios - the first relates to a go-around, the second speaks for itself.
FFF
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