it seems a factor, I remember having a conversation with someone on this forum before about it. With Poch and AVB who like to play pressing, possession based football a small pitch is not good as teams drop of us and we have less space to play in between and in behind. Our pitch probably suits either Harry style quick counter attacking or Spam style bully boy football, to play an expansive game it helps to have an expansive pitch.
That being said it is only a factor and cannot cover for our mental weakness, also AVB and Poch should accept a slight tactical change if the pitch doesn't suit their style, a certain degree of counter attacking football might be no bad thing at the lane.