Earlier quoted context omitted.
I don't think that is really a factor, nukes only really come into it if you have an irrational regime that would rather be destroyed themselves than outright lose.
Russia has strategic as well as a tactical nuclear weapons. They have repeatedly stated that they will use tactical weapons to make up for any shortcoming in conventional forces. An example could be nuking a large staging area or aircraft carriers. There's nothing irrational about it, once war progresses this far.
The premise is that when the Soviets decided to invade they'd lob a few of these at their forces and pin them down for a little while, so the rest of NATO could mobilize.