Comment 24 for bug 1301015

#7 is not important, it's simply wrong.
man ifupdown, then complain.
For ifup it is enough that interface is present and configured in /etc/network/interfaces. Or you can just tell to start all configured interfaces.
For ifdown, you could always use -f.

VirtualBox argument is... just... I have no words. I'm laughing.

TL;DR: A bug report from someone, who never read, what system tell him, doesn't qualify as opinion. Much less a bug.