I'd rather have Shane Williams and O'Driscoll proved he was better than Greenwood in the 2001 Lions tour and countless times after that.
Countless times, are you being serious? In that dominant england era greenwood looked every bit as good as o'driscoll. I seem to remember greenwood being a focal point of the team that beat ireland 42-6 in the grand slam decider in world cup year where o'driscoll was pretty much non-existent in the game.