A model used by authors that could be used by game designers.

We used to have a thing here at BGDF called the Game Design Workshop which is similar to what that critique circle sounds like. 1 person would post their game rules, and would be "in the spotlight" for a week. They could ask for specific feedback (for example about a particular mechanism in the game), or just general critique. After their week (or was it 2?), the next person would go. A moderator was sort of in charge of deciding who would be next, and the more you participated in critiquing other people's games, the higher priority your game would have.

I've been meaning to try and re-implement this here - it's been a long time since it's been done. If you search the archives you can probably find some interesting threads about people's games. I know I got some good feedback from them!

So, who would be interested in this?

I think I'd be up for it. However, my memory of these, they were less about playtesting and more about reading the rules and giving feedback. Which is, of course, useful, but not as useful as playtesting.

The one advantage that novels have over games is that essentially it doesn't cost anything to read a story, whereas there can be a substantial time investment in putting together a PnP prototype (for example, a game I'm working on currently includes a deck of ~60 cards, and asking people to cut and paste those together could be prohibitive). Although, maybe this is less of a concern for most games than I realize, in which case maybe I'd say go for it.

If this starts going, please message me. I'd be happy to join in.

The sites for writing sounds like a great idea. Thanks for letting us know!!!