[mpa000]

I stopped reading when it referred to SPF as "Sender Protection Framework." As usual, the discussion on HN is far better than R'ing TFA.

We recently had a collision between the practices of one of our vendors, the silly way that .edu's tend to forward mail, and Gmail's DMARC policy. The vendor is doing everything "right" in terms of their own (completely transactional) mailings on our behalf but some still want to blame them for poorly forwarded messages sent to .edu addresses that subsequently get swallowed up by Gmail and are never seen by the authors or referees.

[discreditable]

I've seen the same issue with an edu address using office 365. The user set his mail for our org to forward to his .edu address. The .edu address was set to forward to his personal Gmail. The Gmail at the end of the chain was rejecting the mail because the edu didn't rewrite the from address.