( look at those DKs behind me, there are so many of them. To win a war you must understand your enemy positioning & activities well.)One needs an aerial view of the farm (on the roof top) to understand the surrounding and the placement of the entrance hole, the size, the height, etc in order to rectify the problems and give recommendations.
How could one solves or revives a failed farm without even going up the roof? It is not completely done if without seeing from the roof top. " How many actually do this?"
I'm sure you know what I mean.