Interesting. Puffies are very chilled out snakes when you come across them in the wild in my experience. I did some work on a nocturnal species at one point and encountered these guys a few times and in each case nearly stepped on them before realizing they were there.
The scent aspect does shed some interesting light on an encounter that has perplexed me for a while: I saw a bat eared fox approach a puffy and he seemed very confused by its presence. Kept sniffing it as if to try and confirm what it was, even after the puffy started 'puffing.' Cool article, thanks :)