IIRC Buckley started at the helm in 2006, which was clearly his worst draft (but still not bad considering it produced Stubbs and Heisey, as well as fringe major leaguers Turner, Valaika, and Roenicke.) 2010 may be rivaling it, as the only two looking like major leaguers at this point are Grandal and hopefully Drew Cisco.
But when praising how awesome these guys have been (and they have been awesome drafters), don't forget a few of the better picks after the first round (Cingrani, Winker, Hamilton, Stewart, etc.)