I thought she was referencing the 2 phase proposal.
well the 2 phase proposal as drawn is one phase.
real 2 phase which is a 90 degree phase shift (per pole, so you divide by the number of poles to get physical degrees)
so anyhow any number of phases more than 1 is constant power unless you have an asymetrical phase shift. 2 phase motors and distribution systems did exist in the 1920's problem being you need 4 wires to distribute it. 3 wires and phases is easier.