Shoaling etiquette Is it rude to stop in front of bikers stopped at a red light if you're generally slower, which will probably mean they will pass you again? What if you are generally faster so it saves you having to pass them?

Yes, it is rude to stop in front of another cyclist at a red light, especially if they are faster than you. That much is certain.

As Carey says, the best thing to do is to just come to a stop behind the already stopped riders. If you do decide to shoal, at least have the courtesy to be faster.