I've spent two weeks on a domain with limited registrar options because their dns manager lied about supporting larger public keys in txt records.

Also I think there was one question that was a mistake, it had a policy along the lines of:

v=DMARC1; p=reject; <stuff...>; pct=0; <stuff...>

I answered that a failing message would have an effect of p=none, but the right answer was apparently p=quarantine. Is that right, considering pct=0? (Unless I was blind and the pct wasn't set to 0 in the question...)

"If email is subject to the DMARC policy of "reject", the Mail Receiver SHOULD reject the message (see Section 10.3). If the email is not subject to the "reject" policy (due to the "pct" tag), the Mail Receiver SHOULD treat the email as though the "quarantine" policy applies. This behavior allows Domain Owners to experiment with progressively stronger policies without relaxing existing policy."

Thank you thank you.