[just another ref]

This is kind of a gray area, is it not? The rule says the team must not fail to have all players return at approximately the same time. PERIOD

In the case play given, the technical is called when B5 reenters just in time to catch a long pass, thus apparently gaining an advantage.

Edit: Maybe not so gray.

SITUATION 12: Following a (a) charged time-out; or (b) a lengthy substitution process involving multiple substitutions for both teams, A5 goes to the bench and remains there mistakenly believing he/she has been replaced by a substitute. The ball is put in play even though Team A has only four players on the court. Team A is bringing the ball into A's frontcourt when the coach of Team A realizes they have only four players. The coach yells for A5 to return, and he/she sprints onto the court and catches up with play. RULING: In (a), the officials shall stop play and assess a team technical foul for not having all players return to the court at approximately the same time after a time-out. The technical foul counts toward the team-foul count. In (b), the officials may permit play to continue without penalty. A5's return to the court was not deceitful, nor did it provide A5 an unfair positioning advantage on the court. COMMENT: Even though neither situation provided A5 or Team A with an advantage, teams are expected to return to the court at approximately the same time following a time-out. The officials should have also followed the prescribed mechanics and counted the number of players on the court, ensuring each team has the legal number of players. (10-1-9; 10-3-3)