I quite agree. But remember, we've conceded 9 goals in the last 3 games in which Coloccini and Williamson have been paired from the start.
Not saying that Taylor is ideal, either. But he's got a lot more going for him.
And? Even the best defenders in the world would concede goals with Smith and Nolan as the partnership infront of them. It says nothing about either defender.
Their performances against Stevenage and Bolton say a fair bit more than nothing. Not nearly as much had Tiote been there, but still.