BktBallRef is most certainly correct...is he ever wrong?
Check out Case Book 10.5 SITUATION J
Ruling:..."Whenever the coach has been charged (directly or indirectly) with a technical foul, he/she has lost the privilege of using the coaching box for the entire game. The rule is in effect any time the coach personally commits the infraction directly or when it is charged indirectly because of illegal acts or unsporting conduct by bench personnel."
Also check out Rule 10-5
Coaches'Rule, under PENALTY:..."When the coaching box is being utilized, then the first technical foul charged directly or indirectly to the head coach results in loss of the coaching-box privileges and the coach shall comply with the provisions of Articles 1 and 2" (...remain seated on the bench at all times...with exceptions) "for the remainder of the game."
RD