My first T of the year
 

Nothing exciting, though. JVG, administrative T.

Midway through the first quarter, H23 enters the game. Ball gets halfway down the court and the table starts buzzing. I’m C table side in transition, so I hit the whistle to see what’s going on.

“23 isn’t in the book.” Fortunately for H, V had the ball anyway. Coach offered his mea culpa, we shot moved on.

Really?
 

So, the ball was made live (given to player for throw-in), inbounded, then the table informed you of a player who was not in the book?

Once the ball becomes live, it is too late to penalize.

No, because the book needs to be changed. They had not changed the book yet.

For changing a marked starter.

hrm.

Really? So now that player has played without being in the book... scorer informs they are not in the book... it is when the player is physically added to the book that the penalty must be enforced?

So, if in your OP everything had been the same, but the table buzzed to inform you that they had just added the player to the book... it would not have been a team technical?

Case play 10.1.2 Stituation: (b) ... during a time-out in the second quarter of play, the Team B coach requests the scorer to add a name to the team list or change a team member's number in the score-book. When is the penalty invoked for this administative infraction?

Ruling: The infraction occurs when the scorer is advised to add to or change the scorebook. The foul must be charged when it occurs and enforced when the ball next becomes live. Once the ball has become live, it is too late to penalize.

OK, I'm getting closer...

Your sitch. Player enters... no action with the book. Ball becomes live... table informs... action is taken... scorer is now advised to add player to the book. Admin T.

Another sitch. Player enters... coach says, "hey add 23 he just got here"... scorer complies... ball is made live... other team's scorekeeper informs other team's coach that 23 is not in book... coach calls time to raise issue. Now it is to late to penalize. Book was advised to make change and made change. Ball had become live with the player already added to the book.

Correct, although I believe there was some disagreement here on whether it would be too late.

Penalized when they occur/add to or change the scorebook
 

3) Penalized when they occur, after ten minute time limit. The infraction occurs when the scorer is advised to add to or change the scorebook. The foul must be charged when it occurs and enforced when the ball next becomes live. Once the ball has become live, it is too late to penalize. A maximum of one technical foul per team regardless of the number of infractions for 2a, 3a, 3b, 3c, 4a:
a) A team shall not add a name to the team member list after the ten minute time limit. Team technical foul. When such a player legally enters the court, the player’s name, and number, must be entered into the scorebook.

I believe that this means that the infraction is not for the player participating with no name/number in the book. The infraction is for adding a name to the book. If the scorekeeper, for some reason, adds the name/number on his own, then the, "The foul must be charged when it occurs and enforced when the ball next becomes live. Once the ball has become live, it is too late to penalize." comes into play. That's the best I can offer, and I've been working on these type of technicals for a couple of months. It's a goal of mine this year.

bMac, your work in this area has got me focusing on it as well. I feel like I'm getting closer, but still not proficient enough.