FWIW, either last year or the year before SSA held an online Q&A for expatriates. I did manage to get the representative to answer my question, which was why not use MYSocialSecurity, instead of the unreliable letter system. He said then that that was what they were wanting to do. There have been some additional functions added to the site, but of course the Form 7162 is not yet one of them. But at least some change is taking place. Maybe before I'm dead, I'll be able to verify online instead of using mail.