It was hard to believe for me, too. And I didn't stumble upon it; I looked for it closely, and that was a point in the note. People did not look properly for nearly three decades. Many things have changed, but we computer people are still using the same tools. I am not saying old is not good; the current solutions are great, but what are we, if we don't look for the better?

Yes it is that much faster, and a good part of it is because of the multi-thread design, but as a reminder, WinRAR or 7-Zip are too multi-thread, and you can see the difference. To satisfy your doubt, I suggest running Pack for yourself. I am looking for more data on its behaviour on different machines and data.

Can I ask why do you need a version without ZSTD? If you are thinking that compression slows it down, I should say no. Pack is the first of its kinds that "Store" is slowing it down. Because its compression is smart, it will skip any non-compressible content.

On the same machine and the same Linux source code test:

Pack: 194 MB, 1.3 s

Pack (With no Press): 1.25 GB, 1.8 s