It should never be taken for granted by any manufacturer of computer upgrades that the consumer has another machine to use as well.
Which we don't do. The DENEB can be installed without another computer being available.
If a program that is necessary for the hardware being sold requires another program to function properly it should be included.
Erm. Sorry. Everything you need to get a DENEB fully working is *included*. After installing (and the installer is part of the operating system!) you can easily read the AmigaGuide documentation. Even if you don't have MUI installed (and I guess many people have it as standard nowadays) you can startup the Poseidon USB stack from scratch in CLI, and with the included fat95 you can also mount USB sticks from PCs, in case your Miggy doesn't have Internet connection (which would also be possible with DENEB from scratch, BTW, but don't blame me now for not including a TCP/IP stack :-) )
I would understand your point in case you bought a certain "USB2 highspeed" PCI card for a certain PCI busboard from a certain retailer in Poland. In this case, really a crucial part of software is missing (and can't be added, so it is a real severe problem).
Just to give you an impression: for Fast Zorro II development I had to setup an A1200 from scratch, with only a diskdrive (for OS3.1 installation), and a DENEB. My PC doesn't have a disk drive, so all had to come in on either an USB stick or the DenebInstall: harddisk - which worked. And which was the goal - you should be able to get a virgin Amiga system completely equipped with working USB by just inserting the DENEB in user mode - that's opening all possibilities.
Michael