Sorry, I disagree. Splitting lanes is always a bad idea in my opinion. It's a good way to get drivers pissed at you and to me, it seems like you're giving them permission to pass you at the same distance when you're moving. I always take the lane at stoplights. Although the issue is split in the commuting section. Half take your idea, half take mine, so we probably shouldn't discuss it here. Although I will say that your idea is the one adopted in the UK, with specific bike markings where bikes sit at the front of a stoplight.

I love the train horn, although it's probably dangerous. I'd imagine it's pretty easy to blow an eardrum out with that thing. (Train horns hurt my ears when they go past.) The airzound sounds pitiful in comparison hahaha.

In the situation in the OP, I probably would have just sat there until he moved, I'm generally not in a hurry.