Can I restart the "A Shattered Crown" quest at Act I multiple times and check wether four crypts spawn instead of three, to get into Development Hell? Or is there some mechanic preventing you from cheesing your way into it? I really want to check the place out and grab the achievement. :)
Yes, you can - and in fact this is the recommended method to find the place if you're looking for it and its feat of strength - Smash! Jay, Smash! It's recommended, however, that you leave the game while still standing in the graveyard without entering any of the crypts - when you restart the game, you'll still be there, making checking for crypts that much quicker.