Unplugging the network cable during the installation in Vista

[wwwhch2004]

Unplugging the network cable during the installation in Vista causes to the user to wait 5-6 minutes to get a message that the "installation is interrupted, because of the loss of the network".  During that waiting time frame Vista's download bar had an animation, which creates impression that the download is in progress (fake download).
However I went to a download.com and tried to download heavy application , then unplugged the cable from the PC during the installation.