Not all email systems support "+<label>"

[roverwolf]

The method of resolution for an email address using "+tag" as a suffix to the local part of the email address is problematic and will not work with a large number of email systems.

I would suggest removing the following requirement in the resolution process, the subject line requirements are probably enough:

did_method_tag/index.html

Line 481 in ad066b9

<li>Replace the at-sign ('@') with <code>+tag@</code></li>