So one guy stood up and asked why our main page is not compliant with W3C guidelines (doesn't pass HTML validator test). L&S answered that they need to shave off any unnecessary byte, so that it loads faster. That's why they didn't care about closing tags etc.
How the world and perception has changed since that time... It's just sad that one needs a huge JS framework just to build a simple website these days.
Oh and the size of the homepage was in the order of 20 KB then, IIRC.