I just figured that out myself a couple of days ago.
I leveled the Thorns Crusader using the starter set and got to T11 but my wrists started bothering me. It requires a lot of clicking. I tried switching to the LoN bombardment build but that's even worse, I move so fast it's hard to keep him on track and doing what I want. Awesome progression build, crappy farming build.
So I made a Gem of Easement, threw it in a Furnace and leveled up a Monk & Wizard to 70 in an hour and a half each. I decided to go with the Monk, the kinetic feel of the build is just fun and it's highly mobile. Unfortunately the lack of a free set is majorly slowing me down. I can clear T4 easy enough but I don't have any sets yet for him, just a bunch of ancients that I needed to modify the Str->Dex from my Crusader.
The free set for the seasons was a brilliant move. I could never muster the patience to get that far and that gives such an immediate burst of power after each acquisition that I got addicted to D3, which never happened before.