I wish I could add an image to my post - I could show you what happens when I view a long thread (anything with more than 20 or so posts).
Basically, some or all the text disappears from a few of the posts (usually short ones, but that could be coincidence). I see a blank spot that's the same length as the post would be if the text were there. Sometimes, half of a line is displayed - usually, the top half of all the letters in the line. Very odd.
This weirdness usually happens "below the fold" - that is, when I scroll down to see past the first screen, one or more posts just under the originally-displayed portion of the page are likely to be blanked out. Scrolling up or down again doesn't fix the problem.
I've discovered that if I mouse over the blank post (as if I were copying the text), I can sometimes see the text as it becomes highlighted. But it kinda blinks in and out, depending on the mouse position. I can't ever view the entire post and the poster's name.
I'm guessing that there's some sort of complicated programmatic stuff going on with indented or long posts, and it's just not working for me and my browser.
FYI, I use an older computer running Windows 2000 (too busy to upgrade) and IE 6.0 (ditto). But it's not *that* old! I'll bet I'm not the only one with an aged setup...