> Remember when it was a good idea to cache the .length property because it was O(N) on some browser (I think an early IE), so you'd write your for-loops like this?

I do not, mostly because I came online at a time that Internet Explorer was already uncool and Mozilla was clearly better, and also I had no idea what JavaScript was ;) But I can only imagine what the browser monoculture of the time was like, viewing the echo of it many years later with Blink.