ASA 2-Person Slow Pitch Mechanics Question

[HawkeyeCubP]

Knowledgeable Slow Pitch Umpires -

What is the logic behind having the BU take the lone runner (on 2nd) on a tag up into 3rd? (p.245) This seems like it would be a lot easier for the PU to pick up (thereby allowing the BU to simply button-hook in and take the BR around), especially on a fly ball to center or right field. I ask this because from my starting position behind and to the side of the 2nd baseman, who generally all play slight variations of being about as deep as humanly possible without being even with the outfielders in men's leagues, this requires a sprint, and a long one at that, to get into position to get inside and see the catch and tag-up from 2nd. Not to mention the fact that, depending on where in right field the fly ball is caught - for instance near or outside of the foul line - it requires even more distance to cover (having to be more toward the 1st base-home plate side of the infield,) to avoid being in the path of the throw to 3rd.

Anyone have any insight into the reasoning behind this mechanic? With all of the button-hooking I already do as BU from the grass in men's league games, it seems like this would be a good one to pass on to the PU, allowing me to do a normal 1st base-oriented button hook, instead of sprinting across the infield from the right field grass.