How to reset forgotten root password in vSphere

Ran into an issue today with ESXi 4.1 hosts that I forgot the root password for.  The hosts were operating fine in the vSphere 4.1 cluster.   However,  I need to upgrade the hosts and may need to add them back into a new cluster,  which would require the root password.   I Googled "reset esxi root password"  and came up with this VMware KB article:

This line was discouraging:  Reinstalling the ESXi host is the only supported way to reset a password on ESXi.

Not one to give up,  I remembered that ESXi hosts can be configured through vCenter to use Active Directory for host login:

I successfully joined the three ESXi 4.1 hosts to AD,  created an ESX Admins AD group,  and added my AD account to the ESX Admins group.   I then was able to connect directly to each host with the vSphere Client using my AD account.   Once connected to the hosts,  I clicked on the Users and Group tab,  clicked on the root account and changed the password.

Crisis avoided.