Yet another Helmet Question

[bossman72]

A Team B player's helmet comes off with (a) 4:00 or (b) 0:32 left in the 4th qtr.

What do we set the play clock at?  40 or 25?  Please provide a rule or interpretation reference.

Thanks!

[TxSkyBolt]

From the new rules addendum:

c. 25-Second Clock
(New item)
13. An offensive team player’s helmet comes completely off during the down. The play clock is set to 40 seconds if the helmet comes completely off a player of the defensive team. [Exception: If there is an option for a 10-second subtraction in either half the play clock is set at 25 seconds for any player.]

[El Macman]

From the new rules addendum:

c. 25-Second Clock
(New item)
[Exception: If there is an option for a 10-second subtraction in either half the play clock is set at 25 seconds for any player.]

Which leaves the door open for abuse. At 0:50 (4), B44 could "lose" his helmet, and get the clock stopped, momentarily. Even after the 10SS, which leaves the clock at 0:40, A has 25 seconds to snap the ball. Team B somehow manages to hold A on 4th down, gets the ball with 0:08 or so remaining, throw s a TD pass or kicks a field goal to win the game, when A should have been allowed to let the clock run out with a 40-second play clock (as they would with an injury). Yes, a very specific set of circumstances that would be very unusual, if not rare, but certainly possible. 

[Diablo]

From the new rules addendum:
c. 25-Second Clock
(New item)
13. An offensive team player’s helmet comes completely off during the down. The play clock is set to 40 seconds if the helmet comes completely off a player of the defensive team. [Exception: If there is an option for a 10-second subtraction in either half the play clock is set at 25 seconds for any player.]

I trust y'all realize that setting the play clock is governed by which team had the ball when the helmet came off (offense vs defense) and not A vs B.

BTW   Shouldn't it be a down clock, not play clock?