The page is 1.03KB of HTML and ~1.5KB of CSS. The HTML has about a dozen lines of Javascript in the footer that, at a glance, seemed only to execute onclick to do something with the menu. I'm pretty sure a 166Mhz (with an M) Pentium could process 1.03KB of HTML and render the page in under 700ish ms, so I agree that that seems oddly slow for any modern device, unless they're browsing on a mid-range Arduino.