I don't think I'm at all getting my point across.
As a human, you intuitively understand what a door is. You know that it opens and closes. You could recognize different styles of doors quite easily. Even if it doesn't have the same shape as a door, you know that because it has a doorknob and a hinge, it opens and you can go through. However, an alien (if alien enough) wouldn't have a clue what the heck he's looking at because human doors are meant for human hands, and a human range of motion. If they had no understanding of our culture, they might think it's simply a bump on the wall. Maybe we hang our clothing there. How would they know?
Similarly, people that have not been used to playing space games can pick out unusual things better than we can, because we are
used to space games. We intuitively know how to move with the mouse and keyboard, and we know what keys to try to figure out how to get it to work. We know that left-clicking with the mouse is probably the fire button. Someone that doesn't play space games (or, indeed, games in general) wouldn't be exposed to that. This makes them better candidates for this sort of thing. Because they don't have expectations of how it should work, they're more prone to being confused, and breaking it by accident.
More importantly, I think any one of us would almost certainly look at some things and just assume, "it's odd, but usable. It'll be better in the beta" when one of these non-fans would say "Your game is weird, fix it fast".
But it's possible I'm still not getting my point across. That's fine. My other reason was the main
reason for saying that forumites absolutely should not be allowed to touch alpha: PR, naturally. After all, I'm the one that would have to explain to everyone why they couldn't play it early, and I expect a lot of them would be unhappy and/or angry. "I waited five years, and I don't get in on the alpha just because some people with too much time on their hands hung around the forums long enough to leech the game off the developers?!?" is something I'd expect to hear.
There's also the fact that it's easier to keep things quiet and private if you're close friends with them - and I don't think any of us can say we're "close friends" with Josh.
But, on the other hand, it's important to note that this is all just my opinion.
I have absolutely no idea what Josh's plans are, nor can I say I'm undeniably right or wrong in any of my assertions.