That's a fair point.
And maybe having her hold more rallies would have worked against her in that case (people not being drawn to her) because there would have been the an increasing emphasis made on the comparative sizes of crowds (which was already happening to some degree).
That puts them in between a rock and hard place strategically - hold more rallies and get lambasted for having smaller crowds, don't hold the rallies and get lambasted for not having the stamina and not being accessible to the people.
In these cases, one wonders if a human in charge of strategy might have made better choices. After all, it was only just recently that a computer was able to outmatch a human in Go (heavily based on strategy) and I'm not convinced that an election involves less strategy and that you can rely on an algorithm to beat a talented human opponent.
And say what you will about Trump, but his strategy this entire election campaign has paid off incredibly for him and he did what most people considered to be the impossible.