The only thing you have to be careful about is the shifters.
Since indexing came to front mechs (for the life of me I cannot see why it was necessary) the leverage issues and pull per click problems are back.
So Shimano road and MTB fronts are incompatible (there are workarounds by repositioning the cable) and I have no idea about Campag.
I run a Record double with a 42/29 Middleburn Duo using thumbies because it is dinky and light. The profile of the cage is not quite right, but is partly made up for by the slacker seat tube angle. You can have problems on some frames with the back tip of the cage hitting the chainstay.
It's very much a 'see if it works' situation. If you are using clicky front shifters, you are probably stuck.
Yeah am using XT shifters the under bar jobbies at the minute, reason I asked is I know that a lot of downhillers have been using shimano Tiagra rear mechs with cheap sram shifters, so wondered if I could mix a campag front mech with my xt levers