The 85/1.2 on the other hand is one of the sharpest and thinest DoF lenses you can get (without standing a mile away) but it's also one of the most outrageously priced lenses.
I don't think it's outrageous, it's just complex to build. Just check the prices of the new 56mm 1.2 Fujilense for the small APS-C sensors. Or check some other fast lenses... on Zeiss you won't even get an AF on it.
The point is to decide wether you need it or not. To build a sharp f1.2 lense is nothing you can simply calculate and throw into the market.
Here you could get a glue about the complexity of the Canonball: http://www.gletscherbruch.de/foto/85er/objektiv.html Especially check the 72 balls to hold the glass.
+1 - and from what I've read - the huge ground glass element in the front is finished by hand. In a world of mass production, anything done by hand increases cost exponentially.
EOS 1D X, 5DIII, M + EF 24 f/1.4II, 50 f/1.2, 85 f/1.2II, 300 f/2.8 IS II || 16-35 f/4 IS, 24-70 f/2.8II, 70-200 f/2.8II || TS-E 17 f/4, 24 f/3.5II || M 22 f/2, M 11-22 f/4-5.6 IS | 18-55 f/3.5-5.6 IS || 1.4x III, 2x III
I only shoot at ISO 100 with perfect technique - should I get a Nikon?