im debating this exact plan as well. in theory it should work.

i already own a set of 10spd campagnolo bar end shifters mounted to pauls thumbies and ive got an almost new 8spd racing triple derailleur set on my wifes road bike that may be replaced with a 10spd compact system.

this would leave me with the perfect parts to a 10spd campy mtb. my only concern is how big of a cassette the racing triple will handle. i havent looked it up.

shifters: