[Nevadaref]

Chuck,
I agree 100% with your clear, concise, well-written explanation. However, I must caution against using the bench personnel reasoning to always tell you when the T is also charged indirectly to the head coach. One exception and one of my pet peeves for years has been that a substitute who either fails to properly report to the scorer or fails to wait for the official to beckon him onto the court is charged with the T, and is still considered bench personnel, but according to the chart on page 72 of the Rule Book the coach is not charged with anything.
For consistency, I believe this should be changed and he should receive an indirect T.
However, I know of no other instance where your rule of thumb would fail and think it is a great way to remember when the coach gets an indirect.