[Carl Childress]

Originally posted by devilsadvocate
Steve, maybe we should assume that the definition of "no further action" would include "the act of tagging out the protected runner". Then there is no contradiction, because we have included the act of tagging out the protected runner as an indicator of "no further action". Yes, other runners could be progressing at the point that you kill the play. So, since you had to kill the play "prematurely", remember to give the runners the benefit of the doubt when it comes to deciding how far they may have advanced.

The "benefit of the doubt" is correct here. The following is a passage from my book Handbook: The Bases A to W, published by Gerry Davis and available -- for pre-order -- now; publication, sometime in December:

The base umpire should make all awards except those where the UIC declares a dead-ball infraction. For example, if the plate umpire rules the batter interfered before touching first, it’s his responsibility to determine the placement of the runners.
Occasionally, the UIC should be ready to assist you. That’s particularly true of an obstruction award.
Play: R1 gets obstructed as he nears third. Because the ball is on the way to that base, the umpire calls: “Time! That’s obstruction.” B1 is hanging out at second. Now the crew must decide: Does he return to first or stay on second?
The current practice in professional baseball allows B1 to remain on second if he was more than halfway to the base at the moment of obstruction. In the Play that’s not likely. But if the UIC is alert, he will glance at B1 the second he hears “That’s obstruction!” Knowing where the batter-runner was certainly beats guessing.

If the umpires work as a team, benefit of the doubt will be a snap to assess.

The book is actually a two-volume look at mechanics for the two-man crew. Its companion volume (simply named Calling the Plate) is printed in the same book, starting from the back. Or front, depending on which you think is the more important.