...The tactical advantage of the ensconced adversary is just too great....
First, I'll say that I agree with the staying put and waiting idea but secondly, in this example, we have to realize that the BG was also HIGHLY trained. Trained to a degree that would be exceedingly unlikely in an actual event. I believe the underlying theory but the performance of a moderately trained GG against an untrained BG would (probably) be better than this. Not better enough for my tastes and not better enough that I would EVER recommend it but better.
Still happily answering to the call-sign Peetza.
The problem, as you so eloquently put it, is choice.
He is no fool who gives what he can not keep to gain what he can not lose.
-Jim Eliott, paraphrasing Philip Henry.