I didn't think that the episode was necessarily as bad as people make out, though I do understand that people would be upset after hyyping up prison v woodbury for half the season, only for nobody to even be injured in the minor skirmish.
However, I think that the series was a bit more realistic showing us the buildup to the fight, instead of just wham bam.
I do agree that the second half of this season was a bit draggy due to the woodbury stalemate, just as season 2's first half got bogged down with the finding sophia plot. However, i think that the writers will rectify this in season 4