Are units like MPa or psi not commonly understood by the science-curious public?

Well no, nor is the term "strength". Is it yield strength, fracture toughness, youngs modulus, etc, etc? Is that tensile, compression or shear you are talking about? Carbon fibre is strong, but how about if you hit it with a brick, then normal wood is "stronger". And then there is anisotropic behavior... This stuff is complex.

There's so many ways to look at timber strengths, and the article lightly covers how their process increases different facets:

> The team’s compressed wood is three times as dense as the untreated substance, Hu says, adding that its resistance to being ripped apart is increased more than 10-fold. It also can become about 50 times more resistant to compression and almost 20 times as stiff. The densified wood is also substantially harder, more scratch-resistant and more impact-resistant

I'm not sure if Specific Strength is something I've ever encountered wrt timber, because it depends on its use whether its compression, elasticity, hardness, or other that determines whether it's good for a specific use. That said, in my country we typically use F numbers, which are (I think) based around a loose series of terms related to stress.

For instance, here's an Oz timber that I know is pretty hard: https://ironwood.com.au/grey-ironbark-technical-specs/

That said "stronger than steel" is what ironbark is renowned for. My brother, a cabinet maker, just made some furniture form the stuff and before the job, his thicknesser and jointer blades were pristine. Afterwards, they're badly chipped. Sparks literally fly when machining this stuff.

> "coffee-table book–size slab"

...an egregious and tortured alternative to using actual units. They made it coffee table sized? They made it book sized? Do all "coffee-table books" come in the same size? Are they using the coffee-table coffee-table book from Seinfeld?

It's worse than a "Library of Congress" quantity of information, or a "football field" of land area.

Would it be so hard just to say "square centimeters", or the more America-friendly "square inches"?

In another article, they have to explain kelvin, "that is, degrees above absolute zero". Imagine it's helpful for younger children.

Thanks for the interesting comparison.

I can imagine the folks who make plywood and pressure treat wood could just add another process and make a new in-demand product.