I think, for me, the exchanges which sound most natural are not necessarily those which follow the exact rhythms of natural speech. If anyone has ever had to read the transcripts of real conversations you know how impossible they can be to follow, because we rely on hundreds of little visual cues which can't all be described. So there has to be a certain compromise to make the dialogue comprehensible, and I would agree that I'm willing to give authors a little leeway like that.

I also have the same problem as the_antichris, in that I write in a fandom whose characters are largely American or Canadian, and my British colloquialisms keep creeping in. Which isn't a problem for Fraser, but it makes writing Ray a nightmare.