[That one laugh answers all the questions he had about the effect this might have on Spike. He feels an unpleasant tingle of guilt. After all, he's not entirely sure Jack would have escalated things if Spike hadn't attacked him. Granted, the vampire was the one doing the biting in that situation but still.]
I was there to help in case he got hurt which, as you may recall, he did. The fact that I forgot my pompoms was entirely unintentional.
I don't expect you to care or want to hear from me. I just wanted to say I was sorry, even if it won't help at all.