Going by the diagram, it looks as if substantial changes in direction are being counted as a new stroke (which is arguable). Look at `r' - I somehow doubt the pen is lifted between drawing one part and the next.

This is correct. I chose this definition of "stroke" for simplicity. It's meant as a proxy measure for "difficulty of writing the letter". A better measure might be "median time it takes to write each letter at an acceptable level of legibility", but that would require a lot more effort. The numerical results will depend on the measure of effort, but I suspect the general point will be the same.

When I was in school I learned writing longhand as a default. Not block letters. This way most letters are composed of one stoke.

So for me, as a German, this article did not make the slightest sense at first. And even having mostly switched to a kind of block letter style, I write most letters with one and max. two strokes.

I could never imagine writing a "w" with 4 strokes.

For me, this will always be one stroke. Four wold be like stoping my car engine at every direction change. Then getting out of the car. Reentry, engine start, change direction. Start driving. And so on.

(Agreed.)

...how do you write a 'z' if that's not one stroke?

Also, I was taught (poorly) to write 'f' as a single stroke. The best picture I can find is here, in the centre of the image:

https://twinkl.co.uk/image/resource_preview_xlarge/T-L-635A-...

I put lines through my zs and 7s. It's uncommon I guess.

Well it wasn't really anything more than a exploration into handwriting and there is a ton of stuff out on the Internet concerning handwriting and there wasn't any mention any other research or tools. It was more of a shower thought written on medium.

Well it wasn't really anything more than a exploration into handwriting and there is a ton of stuff out on the Internet concerning this and there wasn't any mention. It was more of a shower thought written on paper.

hm, in elementary I got taught to write every word in one stroke, except for the uppercase F's and T's and the like. Consequently I found the article to be utterly confusing.