Systemd ignores / overrides 'shutdown -t' delay?

[Jonathan de Boyne Pollard <J.deBoynePollard-newsgroups@NTLWorld.com>]

Ralph Katz:
> There is no "-t" option.

Jonathan de Boyne Pollard:
> In fact there is. It's undocumented; and is one of four undocumented  > compatibility options, alongside -a, -f, and -F, that are simply > 
parsed and then ignored. There is a fifth undocumented option with an > 
effect, -K.
David Wright:
> May I ask what its effect is?
Reboot the system into a replacement kernel with kexec.  It's from a 
System 5 shutdown option that didn't make into the mainstream.

* http://lists.linuxfoundation.org/pipermail/fastboot/2005-June/008429.html