"It could be taken as a matter of faith that there is no God."
It could be, but it generally isn't. To be a devout religionist, you're supposed to be 100% convinced of something for which there is no evidence; it's hard on the other hand to prove the negative, so generally, atheists don't say they're 100% sure. There may be a few who set out to be irrationally atheistic for shock value or something, but I've never met one, and they would seem the exception not the rule (just as suicide bombings and abortionist shootings don't define religion). I'm certainly not sure. Dawkins isn't. I think Carl Sagan put it best: "I don't want to believe. I want to know."
"Irrespective of the existence of a God, there are good health reasons (physical and psychological) for having a belief system."
References? Besides, what's the point? You're not going to convince me or Dawkins or anyone else that we should believe that there's a teakettle orbiting the earth for health benefits, even if we wanted to. It doesn't work that way. But--as the point has already been made--I have a belief system. How odd that one could phrase it such that those without supernatural beliefs are cast as not having any belief!
"There are also sound martial reasons. Rational research supports that. So that's another good reason not to proselytize."
Martial? Christians outfight atheists, etc? I laugh out loud when I see the UFC fighters cross themselves, or, like Diego Sanchez, extend personal thanks to Jesus, who evidently did medicine ball work with him and guided his knee into Karo Parisian's jaw (must be an infidel). Curious to know data. Or did you mean marital? There may be some correlative studies, but you have to be careful about your control group selective. Correlation, is of course, not causation, and there is no evidence that speaking your mind about a scientific approach to the world (ie, a nonreligious one) disrupts either combat or marriage, whichever you were referring to, or whether you believe them related
"Alas as an athiest, you likely won't get the same benefit. It's kind of like being in a control group in a double-blinded RCT, and being told you're the guy who got the dummy medicine."
Funny you should mention the well designed RCT, as there's zero zilch none nada evidence of any such quality that belief in the supernatural is beneficial. As it turns out, the group that got prayer and knew it (in the only good study on prayer for healing) found they did worse, so maybe its good to go placebo here. Once that study was reported, of course, religious figures pounced on it as poorly conceived (science does not comment on faith), but I imagine their editorials would have been different if the study had shown an effect, no? Almost like the post "empty-force" test discussions.
"But there are still benefits to spiritual pursuits irrespective of belief in a diety or dieties. That's part of what we do with these Eastern arts."
Yup--I'm benefitting from my eastern (and brazilian--5 matches tonight and 5 straight submissions tonight on guys 20# heavier, sweet!) arts without faith, and I dare say most Americans, who hold noneastern religious views in general, wouldn't want their karate tempered with too much flavor from other spiritualities, right? (christians, jews, muslims?) I guess it depends on what you mean by spiritual. Lots of scientists use religious metaphors, but they don't often mean that there's a bearded tinkerer out there affecting happenings on earth. Awe for nature and discovery is a clearer term.
"From this point of view, the only difference between a deist and an atheist is that the deist gets their moral code from an outside source (bible, koran, flying spaghetti monster, whatever), whereas an atheist derives theirs from introspection and deciding for themselves."
Well, I'm totally with you in general, but I'm not sure about either asertion. Religious people don't usually get their moral code from their religious books. Dawkins has a great chapter on this in "The God Delusion." There's so much heinous stuff in the Bible that's ignored (rightly so) and then there are key ideas picked out at random (say, enforced codes vs neglected ones from Leviticus) that I believe most religious people get a moral code from their culture and their inner selves and then they justify it with scripture (not that there's anything wrong with that). And atheists can look within for their codes, but of course we all derive what we believe from what we're taught, in large part. For example, my ten commandments would START with the golden rule. That was taught to me by Christians. Doesn't make it bad at all!