John Lam, the guy writing IronRuby, cannot look at the Ruby source code. That is the way Microsoft works. This is setting yourself up for failure, hard.
The main issue that I have with this is that this is purposefully putting blinders on, and then acting surprised because the direction that the project went is rejected by the community.
The Entity Framework debacle is a good example. How the hell can you miss what is going in the OR/M world for the last 5 years? How the hell can you get to the point where you are surprised by the need for persistence ignorance?
Well, the answer for that is simple. You don't look at what is happening outside. This is irresponsible behavior at best, and the reason of a lot of the angst with Microsoft.
Oh, and another thing, if you are actually going to do something in a certain field. Don't go and ask people that have never been in this field. It is highly recommended to ask people who are actually doing stuff in that field, so you can get experience. That way, you don't have to repeat all the same mistakes.
MS MVC is actively doing the reverse, but that is only one project, but I hope that this approach will spread to other teams as well.