Even with 100T it's hard to find a block, luck is still very much needed. I've been trying for a few weeks running 50 - 100T with no joy and only a few decent high shares.
I was kinda tongue-in-cheek there, but sure it's all luck. You can run 100T and never hit and then some guy pops up with an old Block Eruptor hashing 30Mhs and he gets a block in 15 minutes. It's one of the things that makes Bitcoin so equal and attractive to the little guy and the big mining farm alike.
Absolutely. I've rented hundreds of TH and hit nothing and then had my S4 pull a block, you just never know but it's a rush when you hit
Sure is..:-)