Well. Developer hate writing documentation in general even they got paid to do so. Their argument is that source code is the best documentation you'd ever have.
I know that's BS as I were a statistician developer. The code is enigma behind the complicated math model. If we don't write any good doc to explain our ideas, our jobs are saved. There is a funny story about CITI bank. They fired all their Quants in financial crisis who works on their credit default swap and CDO in-house pricing. You know what nobody understand how their code works.
But I believe there are enthusiast who love to blog and share their ideas and finding. We only share pieces here and there. We are not asking for writing a book about this. Like the page from kataetheweirdo http://www.emaculation.com/forum/viewtopic.php?f=20&t=9099
If I can find this, that would save me and others a lot of time. I know the one who write their codes have gone. They won't maintain it or write anything. But I believe someone will.
The key is to:
1. Make it easy to access -- that implies searchable and developers who know a thing or two can notice it. May be add the link in macemu git repo.
2. Democratic writing process like wiki
In fact, macemu github allow you to write wikipage. It should be the better place to start. https://github.com/cebix/macemu/wiki/Developer-Guide