YW, all. I, too, learned even more from this, for I didn't realize the blue/red scrolling effect (which might be what makes it worse in a fast chat, since so many of us use blue.) And though we don't have the purple/yellow problem because the yellow isn't readible... I never knew about that combination.

I have, over the year, tried to figure out why sometimes a little bit of red font in chat didn't seem to cause any major brain problems, but only visual... and now I guess it was depending whether is was combined with blue font too! Kewl.

In reading that article, I also found a suggestion to the photosensitivity of my "flicker vertigo" caused by even simples things like tree trunk shadows along a roadway in early morning or early evening... it said, close one eye. I had been doing that just to try prior to finding this article! I also know to change speed up or down, so that the flicker changes... not all speeds create the same problem.

I haven't 'seen anything about boldtype causing problems other than that listed about, not being able to "find" docjohn's comments in chat... but there has been studies done on the legibility of writing in ALL CAPS and found that it is much more difficult to read, and slows the reader down extensively.