Had a flat rear tire on my Bianchi road bike with full campy and wanted to go on a quick ride with the family, so I slapped on my race wheels which have a shimano cassette. We went on a 4 mile ride and I had no problems. So what gives? I thought they were not supposed to work together?
You’re not the first person to find the shifting adequate between the two groups. However, I doubt you were really pushing it like you would on a threshhold ride.
Anyway this site has all sorts of info on cassette pitch, derailleur ratios, pull amounts, etc: http://www.ctc.org.uk/desktopdefault.aspx?tabid=3946
In general Campy 10 speed and Shimano 10 speed are something like .2mm different on the cassette per gear so thats pretty minimal.
It works fine. The spacing with 10-speed campy and shimano cassettes are very close. Had I realized this earlier, I could have saved myself some $$$.