But then, how can a simple heuristic like "hey, this guy has sent and received messages from this non-google address before, we should most definitely not drop incoming mail from there" not be in place? I gmail is pretty much the only google service I still use. In pretty much all regards, google has repeatedly disappointed me over the last couple years. A couple months ago, gmail suddenly started dropping incoming mails from a mailing list I've been subscribed to for 8(!!!) years, three times so far. Exactly like in the linked blog post here.

To sum it up: sorry, but what you're saying here doesn't sound like it's true, and if it is let me tell you that you're failing at it, miserably. The only reason I didn't move away from gmail is that it's just a lot of work. But the time will come, eventually.