I understand no trade is 100% fair, and if he was playing in a 12team league I wouldn't veto it(Because higher end pitching is much harder to come by)(still consider it horrible). But in a 6 team mixed league(where everyone carries 4), pitchers as good as Dice-k can be had off the waiver wire.
This is the 12team league equivalent of trading ryan howard for claudio vargas(or shawn hill, chad durbin, or boof bonser etc etc) or someone else who is WW material, or borderline WW. Which is basically player dumping.
In his league this is the equivalent of trading a 1st round player for a 9th or 10th round player, Straight up. Thats highly vetoable to me, unless there are outstanding circumstances like gruesome injuries, ridiculous prolonged slumps(andruw jones,lance berkman) etc.
Obviously I am not the only person who thinks it should be vetoed, since your league vetoed it. Everyone is entitled to there opinion and I am atleast backing mine up with some reasoning.