That's cool Deano, it's been discussed many a time as you say.
The biggest problem is that guys don't consider how many differences between the various tyre manufactures, meaning their tyre profile is or can be so much different. You can put a 200 Dunlop on and it will feel so different than a 200 Pirelli, I thought there was something wrong with the tyre at first.
As for Chris's original question, no, I don't think a 200 will necessarily give you extra lean angle, but depending on what you used before, it might.
I doubt you will need more lean angle, on the track I've never run out of rear tyre using a 190. We now use 200's because the profile gives you more side grip, but is harder to make direction changes.