I believe that it refers to the new behavior of the square formation, I dont remember which patch was that changed it, but before troops would stand in a square formation, all of them holding shields in their respective side (front, back and sides), and it was almost impenetrable by any ranged unit. The units were also tightly packed, which made cavalry charges against your troops a suicide mission .Now the square formation turn their shield to their "direction" instead of covering all four sides, and the units in there end up as porcupines, arrows all around except their front. Also sometimes they will create a hole in the middle for no reason and become even more squishy against cavalry charges, which was the only effective use left for the formation. These 2 changes have made it quite useless. This has been the case for quite a while and I havent actually checked to see if you guys fixed it or not, but havent read anything in the patches mentioning it.