The Fifth Element ...
 

The thread on "fifth foul" mechanics got my thinking.

Blue team versus white team. Each team has an all-state seven footer, while all the other players, on both teams, are six feet, or less.

Third period. For whatever reason, blue has used all of their timeouts. For whatever reason (catch their breath, don't pick up another foul, etc.), both seven footers are on the bench. Blue has a six foot forward at the table ready to substitute at the next opportunity.

White's five foot two point guard picks up is fifth foul. Official reports the foul to the table, is told by the table that it's the player's fifth foul, the official tells the white coach about the fifth foul, and then tells the table to start the twenty second replacement clock. Warning horn sounds after five seconds. A split second before the twenty second horn sounds, white coach sends in the seven footer to replace the little point guard. Official beckons in both the white seven footer, and the blue six foot forward.

It's too late for the blue coach to send in his seven footer. Now the white team has a distinct advantage with nobody to guard the seven footer.

Is this the way the replacement rule works? I know that the replacement interval is not a timeout, but I'm often perplexed by the subtleties of this rule. During this twenty second replacement time interval, when can we let substitutes in, and which substitutes can we let in, and when is it too late to let anybody in? Man, I'm so confused. Please help me.

It's never too late. Why would it be? You have a dead ball and if someone runs a sub up to the table, you're bringing that sub in.

The exception would be on a multiple shot foul -- if the sub isn't waiting at the table when you bring in the replacement for the DQed player, he waits until the normal time to come in -- which is still before it would really matter.

Anyone can sub during the interval. Think of it as any other time you allow substitutes. What's so difficult?

I think he is comparing this to the warning horn just before the end of a timeout...

I concur with the others. The 20 sec interval is not the same as a charged time out ... normal substitution rules apply. Sidenote: what can't or shouldn't happen is grant a time-out to either team until after the sub for the DQ'd player has reported.

Stupid Warning Horn ...
 

Thanks guys. rockyroad hit the nail on the head, it was the warning horn after five seconds that was confusing me, and, as you all know, after my 11,000 posts, I'm easily confused.