[alan_cx]

My instant thought is that the bold headings draw the eye away from the bit you are currently reading.

"You" read the first heading, and decide to read the plain text below. As you are reading that, your eyes notice another heading below what you are reading, and if the paragraph you are currently reading is not holding your attention enough, the next heading gets your attention. Your eyes then leave the paragraph you are currently reading because the heading below it now has your attention. So, you start on the next paragraph and the whole thing loops as you go down the page.

So, I would suggest that one should use headings and attention grabbers as little as possible, make the paragraphs worth reading, and try to get the message of the paragraph across in the first sentence or two.

Does that work?