It would be very useful. Think
d=bigmarketingcompany.com
i=(_at_)brandA(_dot_)bigmarketingcompany(_dot_)com
d=bigmarketingcompany.com
i=(_at_)brandB(_dot_)bigmarketingcompany(_dot_)com
Useful to whom? I have little interest as a mail receiver sorting out
an ESP's different campaigns, and I suspect I'm not alone. (This was
the same fallacy that was behind the failed Project Lumos.)
You're welcome to put whatever tracking stuff you want into your mail,
but I'm going to maintain one reputation for you regardless of the
stuff.
R's,
John
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