When transfering large amounts of data I’d most definitely advise using rsync. Something fails, connection falls and everything is okay as it’ll pick up where it left off.

should be the number of hardware threads available on the system by default

No, not at all. That is a terrible default. I do work a lot on number churning and sometimes I have to test stuff on my own machine. Generally I tend to use a safe number such as 10, or if I need to do something very heavy I’ll go to 1 less than the actual number of cores on the machine. I’ve been burned too many times by starting a calculation and then my machine stalls as that code is eating all CPU and all you can do is switch it off.

So, you’re telling me magnetic taps is not our real end solution? I’m not buying your new fancy ideas.

Dist upgrade is only dangerous for the people who do it. Wait a few weeks before upgrading to the new release and most broken things will be fixed already. I used arch a lot, and I do like the idea of rolling releases, but at this point for the couple programs I need new features in, I just build them from source.