@mattround wait, you can see results in postmaster? damnit, I've had someone getting dinged for gmail spam for a while now, but the couple of outbound mails at gmail "weren't enough to generate any info or stats" for postmaster tools. swore a bit when I fixed it by adding in a dns dkim entry that by standards wasn't needed, but it shut up gmail anyway...
(yes, it's always DNS, even when you've followed the rules, because sometimes somewhere just wants a bit extra for funsies)
@mattround gmail pointed me at that for troubleshooting, got the domain enrolled etc fine, but never any data at all. can't imagine the fun of trying to funnel actual mass emails through it :/