Which is a pretty remarkable finding, all in all. At least some dyslexic kids (20% in this study) are helped by something as obvious and easy to fix as providing visual relief in the form of whitespace.
I have found that wider fonts and more spacing (both side-to-side and top-to-bottom) give my eyes great relief when reading, and this has to help with comprehension, focus, and staying on task. It’s why I really do not care for fonts like the ubiquitous and tension-filled Arial and instead prefer wider, more relaxed-looking fonts like Verdana.
And this is not limited to reading; ask any experienced software developer: whitespace is good. Using whitespace to organize computer code and embedded comments in easily and quickly scanned chunks makes for better comprehension. Computers and compilers might not notice the difference, but human beings sure do.
For most of us (but probably not all) our eyes need all the help they can get to pull key phrases, concepts, and meanings from a big mashup of characters on a page or screen.
For that matter, ask any advertising or marketing professional, same thing: whitespace is good and enhances comprehension.
Try it sometime in MS Word or even in an email app: format a paragraph or two of text, at least 5 or 10 lines, in different fonts and then try reading it, but also try looking at the entire group of words together as a purely visual thing, as if it were a foreign language. Because whether you realize it or not, your eyes have to wage that battle with everything you read.
Or look sf the visual differences with the old standard of two spaces between sentences vs. the html standard of one space. This was a step backwards, not forwards.
I’m not “into” fonts like some people, like those who take up the cause of eliminating the scourge of Comic Sans from the Earth, but this is just more evidence that the overall spacing of text on the page (or screen) definitely does make reading that text easier or harder – and why make it harder?