[niconii]

Were the five unclosed runs before the five closed runs? I could see that making a difference vs. interleaving them, if the hardware needs to "warm up" first.

For me, on Firefox on Linux (I know it's the one with the smallest difference, but I don't have the others on hand, sorry), using the "load" time at the bottom of the Network tab, with cache disabled and refreshing with Ctrl+F5, interleaving the tests:

- Unclosed: 1.38s, 1.49s, 1.45s, 1.52s, 1.48s

- Closed: 1.47s, 1.37s, 1.48s, 1.49s, 1.35s

The one with </p> omitted takes about 0.032s longer on average going by these numbers, but that's about 2 frames of extra latency for a page almost twice the length of The Lord of the Rings.

Regarding the page itself, I tried to keep everything else as identical between the two versions as possible, including the DOM, hence why I wrote the </p> immediately before each <p>. As for backtracking, I'm not sure what you mean. The rule for the parser is simply "If the start tag is one from this list, and there's an open <p> element on the stack, close the <p> element before handling the start tag."