[AtlUmpSteve]

My opinion:

1) It was a clear IFR situation; and the rule applies whether called or verbalized or not.
2) R1 clearly understood he didn't need to run, thus recognized it was IFR; he ran later only because he thought R2 had forced a play, and if you start a snowball fight, you may get better results than standing there to get tagged out.
3) Offense gets two base coaches who are expected to tell the runners when to run and when not to run. Umpires aren't responsible if coaches and/or runners don't know what to do.

My conclusion is that a loud, clear, and appropriately timed call probably wouldn't have changed a thing, that once F3 dropped the ball, R2 would have (stupidly) run anyway. There was no jeopardy; the coaches and runners needed to know, call was made prior to needing to make a decision to run or not if ball was dropped, needed to do the right thing, but they (collectively) did the wrong thing. No way I bail them out from THEIR mistake. The play (THEIR play) stands.