I'm afraid I don't see any grounds for action, Splinx. Tony summed up the reality pretty concisely when he wrote:

If you ban off-topic posters you might as well close the place down.
Same with banning people who don't answer questions directed at 'em, but instead go on and on and on...

Digression is natural, and a lot of threads drift away from the root topic. Other times (like the example you give), people make flip comments that, on the surface, don't seem to be addressing the topic. But sometimes I think that that itself is the message--Scott was directing a bit of ridicule at your post. That may be rude, but it's not something I can regulate beyond directing the worst of the rudeness to Flames.

Besides, you said that "this gentlemen" is on your "auto-ignore" list. Why aren't you ignoring him now?

There's nothing I can do for you, Splinx. Relax, keep on ignoring the people you don't want to talk to, keep on posting about the topics that you want to talk about. The universe, or at least the HabitableZone part of it, is unfolding as it should.

--Robert™