(Honest question. I’ve toyed with it in minute detail a couple of times over the past decade, but for fun or as part of matching a lined-paper æsthetic. Not because I think there’s any inherent virtue in it, because I don’t. So I’m curious why you think CSS needs it badly.)
Because the current methods to it are very complicated and only work with a few fonts. A reliable baseline rhythm would lead to better typography and sense of visual order.
More calm
More orderly
Easier to read
More professional
Ah, I think you copied the list from https://zellwk.com/blog/why-vertical-rhythms/. It says these might be properties of “better”, largely without quantifying what they mean, as part of comparing something with simple rhythm (and quite ugly in its spacing, in my opinion) with something that’s deliberately terrible.
To the best of my knowledge, no one has treated “rhythm” in any way rigorously, and it’s mostly just a crock, something that sounds good on paper but is utterly without actual reason or value, rather like modular scales for typography.
I don’t respect that article. Its analogies are lousy, its examples of non-rhythm unnecessarily bad (straw-man arguments), its rhythm not great in any case (and lacking any attempt at anything like baseline alignment), and after the first instance it only really shows rhythm with an unrealistic superimposed grid which obviously makes rhythm look better than non-rhythm. I get the sense that the author has read a bit of various things, and then attempted to justify an opinion in any way they could, and ended up producing an incoherent and completely unsound argument.
There are certainly major places where consistent spacing and sizing is of value. But slavishly following it page-wide without something like a background pattern that you’re aiming to match (which is absolutely a legitimate use case, but is æsthetic rather than functional)… I’ve never come across any argument that seemed to hold any water, and I’d like to understand why a few people are so attached to the notion that it has inherent virtue.
To the best of my knowledge, no one has treated “rhythm” in any way rigorously, and it’s mostly just a crock, something that sounds good on paper
Ironically it does sometimes look better on paper - specifically on cheap, thin paper with double-sided printing where ink showing through from the reverse side in the inter-line gaps can be distracting and unattractive.
So perhaps you're wrong about it being utterly without reason? It makes sense to maintain an exact vertical rhythm in digital typography any time you're displaying your content on a thin, double-sided monitor where the image from the reverse side bleeds through. Not sure how much use it is apart from that though.
Amusing indeed; I was actually thinking about my primary Bible at the time, which certainly benefits from rhythm, including having things like book titles and page headers fit the rhythm. Paginated media can certainly benefit from rhythm, most obviously when double-sided with bleed but even when not, as you flip through.
I meant “no value in scrolled media”, I just didn’t express it so because I hadn’t thought it through carefully enough. Note that digital media can also be paginated; a PDF where you switch pages rather than scrolling, for example, or content that might even normally be scrolled but viewed on an e-book reader, due to the physical properties of e-ink panels; and these things can definitely also benefit from matching alignments and dimensions across pages even without the bleed issue.
Still, even though I was expressly thinking about it, I somehow didn’t connect the dots that maybe this idea of rhythm is a carry-over from the print era. Thanks for pointing out that link!
(My primary Bible is a second edition RSV, where the layout of the first edition was reused and only tweaked where necessary. This leads to minor ink weight differences within some pages, and a very few instances of visibly wonky layout, with elements a fraction of a millimetre from where they should be, or slightly crooked. The most significant weirdness for rhythm purposes is how John 7:53–8:12 was restored from a footnote to the main text, and the column it’s in has one fewer line than normal, with a half-line break between two paragraphs, and the rest of the line’s height distributed through the column’s leading. I’ve been paying a lot of attention to its typography recently, as I start making my own software designed for Bible reading, which is basically a space where there has never been a single option that I would consider good.)
