TD has announced its way of working from the very beginning.
We did not discourage external contribution to IL-2, but wanted to keep it structured, with clear technical standards, relevant content, free of copyright stuff, etc.
You can read it here. Interview from 2009:
http://www.simhq.com/_air13/air_420c.html
It's up to you to judge, if TD has fulfilled it within last 3 years.