Hmm, this would probably mean:

• Tagging the URL's to the links in reply notification messages (e.g. http://www.perlmonks.org/index.pl?node_id=123456¬if=1&msg_id=654321)
• Modifiying the engine so that it honors these extra parameters and deletes said message from the user's inbox.

I have no idea either way, but I have a suspicion that this would put more load on the server than the current situation, for little actual gain.

There are many times I click on the link to a reply to one of my nodes, then go somewhere else on the site and come back to the reply later, through the link. Your system would defeat that behaviour (unless you make it configurable, putting more overhead on the process).

CU
Robartes-