Yes, it is very original mission. Sadly it is not discussed much among players though it certainly strays from usual Thief-gameplay formula (which perhaps IS the cause of it). Surprisingly very dynamic and feels like some kind of single-player Thief-match - since being guard, you must protect valuables from thieves by... "stealing" them first (and under time constraints)! Perhaps the best (and def the most original) mission by Zontik.
The Cabot was made by another author, Flux. He (or she) also made Valley, pagan-themed semi-sequel to Cabot.
As for this mission - I felt it a bit empty from loot in the city part, and keyhunt in the mansion was a bit too complicated. On the other side - some optional quests, and the mission is quite good-looking.
I agree. I like Xorak's next "Zealot's Hollow" and "Little Fly" is very beautiful and plot was interesting (though I don't like the idea of revisiting OM location - the mission was made for one of Reloaded Contests, but was a bit late). But those puzzles... I guess I should have played it on lower difficulties - with puzzles being less complex. I stuck at almost each step, each puzzles.
It seems like CL evokes different feelings: I like MiM because of its challenge and because of "undead event" - which itself significantly changes gameplay conditions. The last mission while not being as good (in fact, it is quite empty and feels disjointed from the main storyline), but still has lots of stuff with the Gaston's hideout and with THAT compartment.