I used to years ago, but eventually wrote a browser extension Paragrasp to do it: https://chrome.google.com/webstore/detail/paragrasp/lhhabjbh... for Chrome and https://addons.mozilla.org/en-US/firefox/addon/paragrasp/ for Firefox.
On the other hand I most often select text at the bottom of the page before hitting Space to advance the page. If you could place a line of highlight across the page before it starts spinning (or jumps) and fade it out gently after - that would definitely be of use.
Or you could think about splitting chubby paragraphs into predictably behaving chunks.
Very nice plugin, thank you.