[greymule]

A look at the history of the rules reveals why they are worded the way they are. OBR long had a rule that an infielder couldn't intentionally drop a fair fly ball in an IFF situation. Obviously, on a popup on which the IFF was called, it wouldn't matter, so the rule was intended to cover a deliberate drop on an fly ball (usually a liner of some kind) on which the IFF wasn't called. Some umpires considered letting an easily catchable ball drop as "intentionally" dropping it, so an approved ruling was inserted that allowed the fielder to let the ball drop untouched. The violation was defined as catching the ball and then letting it drop. Then the question arose concerning guiding the ball to the ground. OBR interpreted that also as an intentional drop, though they never specified such in the book.

It clear that ASA, in considering the same situation, specifically wanted to permit guiding the ball to the ground and therefore put it in black and white in its book. Had ASA not spelled this out, umpires and players could logically have assumed that guiding the ball to the ground was a violation.

If infielders could guide liners to the ground in OBR, you'd see them do it routinely. In the thousands of ASA games I've done, I've can't remember ever having seen a double play completed on a ball guided to the ground, though I don't doubt it's happened.