[eli]

You could just use [e-mail] for the no-alias version. So myname+foo@ works and my.name@ works but myname@ goes directly to the trash.

[gruez]

That can also be normalized.

[joshuaissac]

The normalised version is what gets redirected to trash, according to GP's proposal. Legitimate senders who do not normalise have their mail delivered to the inbox.

[edoceo]

Yea, gotta take all dots out on the username portion of Gmail address

[urbnspacecowboy]

In which case the Gmail user knows to mark mail without any dots in the address as spam.

[eli]

That's the version that goes directly to the trash.