oh I meant the NC clause.
The idea that preventing someone else to sell my manual,
while anyone totally being able to modify, redestribute (non-commercially),
etc.
If I understand what you wrote previously, this is unethical because it's
used to produce a work.
Why is that exactly?
Wouldn't that be possible for the produced work to be licensed
as fully free anyway (even commercial redistribution)?
I mean preventing non-commercial redistribution shouldn't prevent
correction, documentation and/or modification by anyone else.
That's what I don't understand.