Apparently a distinction should be made between receiving and sending: I got Myles' message fine, but when I sent my reply I received the following message because I responded without the "+etc" in my email name. I'm not aware of a way (although it may exist) to tell gmail "always change my sending email address for this mailing list." A better solution might be for the list to automatically parse addresses and say "if name+blah@example.com is subscribed, name@example.com can send to the list. But that is probably tricky too ...

---------- Forwarded message ----------
From: <talk-owner@gtalug.org>
Date: 18 August 2014 13:33
Subject: Your message to talk awaits moderator approval
To: gilesorr@gmail.com

Your mail to 'talk' with the subject

Re: [GTALUG] Testing from a "+" email address.

Is being held until the list moderator can review it for approval.

The reason it is being held:

Post by non-member to a members-only list

Either the message will get posted to the list, or you will receive
notification of the moderator's decision. If you would like to cancel
this posting, please visit the following URL:

[SNIP]

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Giles
http://www.gilesorr.com/
gilesorr@gmail.com