Ah so why are people not doing it? And why people are not usually doing premades? In CE there were awesome fights happened but it was forced just by some earlier provokes based by some guild digging there.
I will tell you why... people tend to follow the easiest way in everything and thats good as it bring us civilisation progress. This and laziness are the best things humans have. Well of course developers are not stupid and they noticed this principle so they brought digging as easy way how to get prowess and provoke PvP (ganking as canceling of easy digging) in the same time.
Bori failed not cause this principle which really works but because of absolutely horrible reputation which came from whiners who could not join Nastra or Futi or other dominant guild. And changes to Bori came too late...