(it doesn't answer your question though, just asks it)
From what I have read, one should:
- change the DNS config of the domain so that it points to the reseller's IP;
- use the reseller's IP number in the VirtualHost directive for the reseller's accounts in httpd.conf.
Please correct me if I am wrong.
for the complete documentation.
To me, the main advantage of this is that you can determine perfectly the data transfer generated by all the reseller's accounts.
But there must be other implications. For example, WHM's function to change the ownership of these accounts wouldn't work.
Of course, the possible implementation of this option in the future shouldn't force us to give an IP-based account to each reseller.