Agree to a point but am willing to bet that if at the end of the season we only keep 2or 3 clean sheets which is what we are on course to do we won't win promotion
While not disagreeing that the team needs to keep more clean sheets in the second half of the season, IMO to a certain extent there is an element of luck when keeping or not keeping the ball out of the net in any given game. In recent matches IMO we have looked pretty comfortable and sides have scored with virtually their first and possibly only chances.
On the other hand teams can keep clean sheets yet seriously ride their luck in doing so, in that the opposition can miss numerous chances. A good example of this is Leeds v Sheff Utd a few weeks back. Sheff Utd created more opportunities v Leeds than they did against us, yet Leeds kept the clean sheet.
Also, however well you defend, you can't legislate for a team scoring a fantastic goal which nothing could be done to prevent it. This was and is one of the big flaws in 'Pulisball' tactics. Nicking 1-0's is all well and good but with a little bit of luck going against you these results can easily swing the other way.
However there isn't a great deal of luck when it comes to being free-scoring, a team is either capable of putting the ball in the net frequently or it is not.
I would also add that apart from Middlesbrough, Leeds and possibly Forest, the other promotion chasing teams have defensive records that are not significantly different from Albion's. (I don't consider having 4,5, 6 goals less conceded over 20+ matches to be 'significant'.)
Score 2+ goals per game on average over the course of a season and a team will be unlucky to not be promoted come the seasons end. We're currently on track for that target.