It's a starting point, but a starting point that directs users to fake italic, fake small-caps, mismatched mono text, inconsistent apostrophes, and ugly underlines. (Oh, and sidenotes and other margin content just disappears on a phone.) If you're going to start from a template, it at least shouldn't lead you astray in multiple ways.

It also doesn't maintain your current position in the document if the viewport changes width, which... I'm not even sure how you break that. The user agent usually does a very good job of handling scroll position.

There's a lot of stuff you'd want to clean up before you let Mr Tufte see it.

I'm not sure what browser(s) or site(s) you're referring to, but just now double checking a few sites in current FF and Chrome I don't see them maintaining scroll position at all. I realize that this agrees with my developed expecations for text heavy pages. Text reflow as the page narrows dominates the viewport position -- content getting longer effectively pushes the viewport up the page. To the user, content appears to flow "downward" as the page narrows.

Do you have an example of a site and/or browser that exhibits the behavior you're describing? I'm quite curious if there's an approach to structuring a page that preserves position sensibly.

We've fixed the fake italics, I think I've fixed the mono text (if you're talking about sizing), I've consistentified apostrophes, and changed how underlines are handled. Sidenotes are still a thorny issue (I'd appreciate any suggestions; we're discussing it in the GitHub Issues for the project) and small-caps are still on the to-fix list.