Yeah, I can totally accept a stretching of their characters in an AU, but... well, when you say "when it's no longer Bodie and Doyle" - do you mean just in name? So as long as someone calls them "Bodie and Doyle", and says that one has curly hair and one short hair etc, then it works for you?

Cross-overs are a bit weird to me too, cos it generally means that one or the other of our lads has been dealt with so that they can't be together! I can get over that, and enjoy a story if it's good, if I know the other character being crossed-over. The only Chief/Pros crossover I really like though is the Jack Reuben Darcy one, for very specific reasons hinging on my first sentence - although I just saw a description of a similarly plotted story that might work for me too... Now if only I could remember where I saw it!