Confusing multiple issues here ..
The question relates to certification as it is referring to limitations ... MFS has the usual story in his post .. which is not surprising considering that he is a certification man. If there is a declared minimum TOW limitation it ought to be in the limitations section but will certainly be explicit in the CG envelope as shown, typically, by a line across the bottom of the envelope at the relevant weight.
In general, pilots would not have any particular knowledge of this sort of limitation as, in the great majority of cases, it is irrelevant to routine operations.
For a practical consideration, the lightest TOW for a given aircraft will be for a stripped configuration, nil payload, min fuel and crew ... but this is not a limitation .. only a consequence of the configuration.