The most interesting part of the Rosay interview was this:
English translation [& notes] by AZR:
The kind of situation that was encountered [loss of speed indication] is a situation that has nothing ... exceptional.
Besides ... when one loses the speed indications, in cruise eh, I think this is the simplest procedure to apply: one must do nothing. And it [the plane] will continue to fly like this for much longer.
I read this as: When one loses the speed indications in cruise do nothing (except keep the aircraft trucking on down the line.) It doesn't mean sit on your hands however.