Bob Wallace states: "We can power grids 100% - 24/365 with only wind or solar by adding enough storage. A 100% solar/storage or 100% wind/storage would not be the most cost efficient solution, but it is possible."

Right.  "... with enough storage" it's "Possible" With sums equivalent to the GDP of a nation maybe. The amounts of storage required to power a nation's grid sufficiently for anything much beyond a power generator's capacity factor is truly staggering. 

The Bob goes on to say "Do realize that nuclear can have only a limited penetration unless we install enough storage to time-shift output from low demand to high demand periods. That's why the world has built most of its pump-up hydro storage. To time-shift nuclear."

What an absolute crock of BS!  Unlike intermittent renewables that only generate electricity nilly-willy, nukes are quite able to ramp up and down with demand. That they do not is a function of economics not technical capability.