Hi, Dean.
] Assuming the router is compromised, so is the MD5 key. And presumably,
] the acls and anything else can be changed as well.
Agreed. My point was to take a few steps to avoid the compromise. 
It isn't difficult to make things just a *bit* more difficult, and thus
avoid the pain caused by the average scan and sploit crowd. Pick good
passwords, limit access, keep routing tables clean, etc.
Thanks,
Rob.