The set is intended to be drafted in eight-person pods, but Verhey said that it also works well in four-person pods
If Dryad Arbor were to leave the format, there might be an argument for giving Green Sun's Zenith another shot, especially considering all of the other cards fighting for the same slot, but until that happens, it's simply too good for the format thanks to its flexibility
The only difference, besides price and mana cost of the cards, is Dark Tutelage is an enchantment
They dont impact the board in any way
Ideally youll fish out another Lhurgoyf and keep the chain going
I say might because it does potentially come into play tapped and telegraphs a bit by needing to be activated before you cast your spell, but it is an activated ability on a land which itself is hard to counter