Oh, I know that letting everyone in on the development process is no panacea. Lest there be any misunderstandings, by "try your hand at it", I meant you should be able to come up with a patch for review. Whether it should be applied or not should definitely remain the decisions of gods who have a (probably) better understanding of the ins and outs of the site.
The code is currently not currently open due to a concert of reasons that it make it unwise to do so. Let me explain.
To make sure patches don't break the site, they have to be tested before they are applied. Unfortunately, since Everything stores the code in the same database as the posts, and stores as nodes just like any other, it is hard to provide a functional mock up of the site for people to work with. The gods have one, but it simply runs off of a backup of the live database, which means whoever has access to it can read other people's /msg's, mail addresses and so on. So the only ones who can effectively test patches right now are the gods. We already have too few of them, and even those we have don't have much spare time. So regardless how many volunteers we do get, we're not going to get any added development speed out of it.
On the other hand, the site is known to have likely security problems. There has never (to my knowledge) been an extensive audit of the codebase.
So if the codebase were competely open, it'd be easier for some people to break things, while it wouldn't be any easier for others to fix them.
I agree with perrin nowadays that storing the code right in the database is not a wise decision. If that weren't the case, everything would be much simpler. I'm not sure how this situation will eventually be addressed and maybe resolved. None of the decisions involved are simle, unfortunately.
Makeshifts last the longest.