In my experience, having used this for a few weeks now, not much scrolling is involved. That's part of the point - more of the text is visible at once, without too many distractions, be they visual or interactive.

Scrolling is a matter of tapping the right arrow key once or twice when you get to the end of a column or the page. Plus, with today's laptop trackpads, scrolling sideways is just as easy scrolling vertically - but, true, it's not conventional.

I feel like quoting "Green Eggs and Ham" - try it, and you'll see! Or not. It's certainly not intended for "typical web content" of videos and bite-size blog posts (and neither is normal Readability). I use it for longer articles and short fiction.

That said, I certainly accept the feedback that many people seem put off by the horizontal scrolling concept. Just thought I'd share!