First the argument was: technical reasons make your grml2hd proposal more complex than current behavior.
Then I spelled out how easy it is.
Next the argument became: your user scenario fails to consider a hypothetical alternative user scenario. But...
Multiple (bulk) install schemes argue more strongly for the idea. So let me close by addressing install scenarios.
only chance to restore the original state is to reboot. :-/
Of course, but so what:
After running grml2hd, what do I likely want? Probably to boot the hard drive and check it out. That means, reboot the PC. This is probably 80% of cases. One drive, one install.
Just to be fair, let's say no, I really want to stay in GRML-CD after setting up the hard drive.
All right, I have just spent 30 minutes doing an install. Assuming there is a magical package missing from CD at the moment, is a 1-minute reboot such inconvenience after 30 minutes? For one package, can't I just apt-install from the net with no reboot? Of course.
The other cases are mass-installs, as Michael said, "you want to install grml again."
What type of grml do I want to mass-install? Probably identical configs to all users. (This is actually my case.) So it does not hurt to remove the ISO packages first. In fact, it helps (read on).
Now let's be perverse. What if I need different package configs for each user? The only way to get them is by hand. Will I prefer to work by hand under chroot from GRML-CD, or by booting each separate hard drive individually? A good sysadmin does the latter. Not only because it's cleaner, but to validate the user systems. Otherwise the users complain to the boss. If I were doing chroot to many drives, things would get confusing very fast (which drive is current chroot?) and I would make mistakes.
Bottom line: Most people will do a single-disk install. The few bulk installers will largely do same-system installs and boot HDs separately for tweaks (if any).
Finally,
Modifying the live-iso needs more "power" than accessing files in the chroot installed on harddisk.
Not in the mass install scenario, which multiplies the pacakage removal task by the number of hard drives (whether chroot or straight). It's simpler to do once from CD and then mass install to drives.
In the single drive case I doubt it's a difference worth argument. CD removal takes slightly longer, but also saves file copy time during copy-all to disk. People can quibble about details.
If you think you don't need the packages "foo, bar, blubs, blah" then just run 'apt-get remove foo bar blubs blah' - but it's on your own risk. Running it in the harddisk system is more safe.
Yes I thought of that. Safety issues by themselves argue for changing grml2hd scripts. But it can be done.
The "bad error/warning messages" derives from debian package management
Some seem like chroot problems to me but - fine, okay, I won't dispute that.
I will leave things here. Argue more if you like, but GRML asked for user feedback and that's mine. I'm a real user, not a hypothetical.
Until the next idea ;-) Mark