Greetings, Werner.

It is good to point this out.
I would make two additional comments.

1. testcd is an essential FIRST TIME test; I think that often, too much time is spent
diagnosing strange behavior of installs that never took the time INITIALLY to verify
the down-loaded iso's integrity in its LiveCD or LiveDVD form. The big KNOPPIX file's
integrity in detail is absolutely crucial to all that follows.

2. It is also true that additions KNOPPIX1, KNOPPIX2,...KNOPPIX9 won't be checked either,
but they are safer, and more efficient storage (in my experience), than is the persistent
store, knoppix-data.img. This applies to cloning LiveUSBs that have used compressed
image stacking, in case anyone's wondering.