Why does USB backend 'Always write USB printer defs, with unknown for devices that are not connected.' ?

Hello,

I had a question about this patch:

http://cvs.easysw.com/cvsweb.cgi/cups/backend/usb.c.diff?r1=1.19&r2=1.20

Specifically this change:

"Always write USB printer defs, with unknown for devices that are
not connected."

Does anyone know why this was done?

In cups 1.1.15, when I added a USB printer in KDE I got a dialog that look a 
something like this:

USB Printer #1
  +-> hp deskjet 5550

Now, with cupsys 1.1.19, when I try to configure a USB printer, it shows 
something like: 

USB Printer #1
  +-> hp deskjet 5550
USB Printer #2
USB Printer #3
USB Printer #4
USB Printer #5
USB Printer #6
USB Printer #7
USB Printer #8
USB Printer #9
USB Printer #10
USB Printer #11
USB Printer #12
USB Printer #13
USB Printer #14
USB Printer #15

I would like to patch our code to revert to the old behaviour, because it seems 
silly to have all those "not connected devices" listed. But it is a mystery to 
me why it was changed in the first place, so I don't feel confidant changing it 
back.Any ideas?

Thanks in advance!
Jeremy Shaw.