I tried this and think I've matched the setup in the Maxwell article, wasn't too sure on the mix operation, liner add seemed to be the most similar though. Very similar render times as well. Only the chair has it.
Thinfilm on the left, 255 white on the right.
Edit: I've just noticed that unlike the Maxwell renders, my thin film reflection is visibly darker, I guess you would also just have to increase the IOR from 1.52 to ~1.6 when using this method.