cs 25.149 says excactly the same thing? MTOW?
it lists a myriad of things in reference to 1.2 Vs, which I deduce to mean the most critical power-plant failure possible...
in any case, other than referring to the regulations, if they don't specify weight according to the Vmc speed, I still have a book based on the JAA learning objectives that specify that more weight is unfavorable in regards to directional control...