Comment 8 for bug 525674

Interestingly, 14.04 seems to be much better at this than 12.04, takling around 1.5 sec rather than 12.
However, it's interesting how much faster it can still be without this.

Here is a measurement I made. This is 14.04 server on the LAN, with ssh-key authentication, and I repeated serveral times:
   time ssh server_on_lan true

With the /etc/update-motd.d/* files unaltered, this takes ~ 1.13 sec
After chmod -x, this takes ~ 0.15 sec.

I hope that helps,