It's a very interesting idea. I really like how you outlined your proposed solution, not like others who mention an idea without any planned action. It changes the paradigm by forcing interaction, which I 100% support. But, that's just me. I don't know how voluntaryists would feel about that.

I'm all for anything that promotes interaction, and if removing the ability to submit a story for a while will change people's attitude, then you have my vote. A few things that popped up in my head while reading the post:

• What if people just go online when the Submit function is available?
• What if people cram submissions all at the same time? That means a lot of great original content will be piled with content that you can find elsewhere on the internet. The 30-minute window would be missed, and only a few would be discovered hours later.

Perhaps, it would be better to have a counter? Let's say for every submission, you need to post X comments and vote on Y number of posts before you can submit again. Some people might game that by just commenting "Nice!" or whatever lame comment and vote randomly on whatever post without viewing it.

Encouraging interaction is really an interesting topic that really deserves to be discussed.