Fucking Internet Explorer... WTF... Anyway, the blog may be unstable for the next little while as I try to fix this. Goddamn it..
I'm thinking it should be possible to either a) detect whether it's going to work or b) failing that, detect the most common too-old browsers1, and insert a fallback. The fallback in this case would likely be that every single post will have a "Continue reading..." link, regardless of whether there is anything below the fold or not. Boo, hiss!
1I adamantly refuse to detect browsers I know are compatible, and then use the fallback if the browser is unrecognized. I have an ideological problem with this. If the website doesn't recognize the browser, it should (maybe) warn the user, and then chuck the HTML at 'em anyway. If it works, great. If it doesn't, use a different browser.