"The Rules Committee did not intend for this to be an up-tempo opportunity for the offense to gain an advantage over the defense. Based on this intent, the officiating crew will control the pace of play on these plays and the following two interpretations are offered for clarity."
This seems VERY clear to me. WE control the pace which means WE decide when A can snap and WE are not gonna let A snap until B has gotten into position. It does not specifically say what we do to control pace, i.e. change ball slowly, take our time getting into position, talk to chain crew, talk to each other, etc etc. But this is clear...dont let A use the clock rule change to gain an advantage they did not have before. Sooooo....in tghe past when would you blow the 25 sec RFP whistle? That is when you wave the U off the ball now.