Mad Men's one mistake

From Panopticist: Mad Men gets all the details right--except one:

...everything is of a piece: The art direction is so immersive that there are no clangy wrong notes to distract you from the rich psychological world the characters inhabit.

Until the show ends, that is. When the last frame flickers off the screen and the credits start to roll, careful observers—okay, just the font freaks—will notice a curious thing: The end credits are set not in the iconic sans serif used in the opening-credits sequence, and not in, say, Helvetica, which was designed in 1957 and became popular soon thereafter, but in Arial, the controversial Helvetica knockoff that Monotype cobbled together in the late 1980s to avoid paying license fees on Helvetica.

Thanks mainly to Microsoft, which has bundled Arial with every version of Windows since version 3.1, this “shameless impostor