I agree with him completely, Ronaldo and Bale won't work.
Especially when you consider both of Madrid's fullbacks are ridiculously attacking and very poor defensively.
Having two people starting from a wide position and floating about not contributing anything defensively would be a disaster.
Which is why i don't understand the move it doesn't make any sense from a balance point of view and would f*ck up the system Ancelotti is trying to build.