I think that's exactly right. Hook's departure is inevitable, and he won't convince First Aid that the merits of the Decepticon cause are worth him joining it. It's a matter of time before Hook's incolvement in the Crystal city incident will become known, First Aid will find out anyway, so he might as well tell him that. It will drive home that he's going - and its out of lingering fondness for First Aid, who he has been close to. Fondness he can't express well.

It's also a way to sever the relationship, but providing some empathy for Hook other than his reasoning as to why the Cons were worth joining. Empathy which not only First Aid but the reader might get for Hook too - as I have discovered when writing about potentially not nice characters (and Hook ain't that nice) there has to be some point at which they can get a readers sympathy, or the readers hate them! I don't actually want people to thank Primus First Aid was shot of Hook - I want them to see it as all rather sad!

Anyway, thanks for that feedback. This was quite tricky to do in the time and what you've highlighted could probably do with clarifying when I've slept on it :P