Email: I have been using SPF in soft-fail mode ("~all”) for a long time. Now I am using DMARC to get reports about SPF 'violations' if that is the correct term. How often do you find that SPF gets screwed up because of stupid servers doing redirects / forwarding and borking the relevant origin information in the process, so that bogus SPF failures are generated?
I think that I read somewhere that one or two big outfits are using SPF seriously. If so, how do they deal with these problems?