Dave, it's my opinion that Heatwole's emails were ignored totally, not because they contained 'no overt threat', but because nobody at the TSA answers or even looks at them as they arrive. Just an auto-generated reply.
...although they can then say that he'd been "under investigation" since the emails showed up. Yeah, I see your point. I just wish it wasn't so. I was having a go at the TSA based upon their explanation. You're doing that awful "reality" thing. Stop it.
Dave