Some years later, I interviewed at Knight Capital, just a couple of weeks before their blowup. (Dreadful interview at which I did dreadfully, being asked to write C _over the phone_ by a supremely uninterested engineer. Quite a red flag in retrospect.)
No pun intended?
I re-read the original paper every few months, more frequently if I'm working on Safety-of-Life-Critical equipment. Which, given my day job, means I'm re-reading it every couple of weeks at most.
Keeps you sharp, doesn't it?