I am not sure - I've made an attempt to show how such a thing might work and there are no doubt examples of this in many other languages and I know Hendrik had some thoughts, we need to sit down and design it and see if its possible.

During the product meeting we discussed this topic we agreed we are going to focus on writing up what the requirements, use cases and such are before trying to design a solution and I am not seeing a clear set of requirements or desired outcomes here.

I'd say this should be one of the desired outcomes and we should then let the right people work towards designing this feature around those.  Without a solid set of goals it's very hard to evaluate the solution.

Sorry for the late reply on this, GitHub's excellent messaging feature somehow didn't mail me your reply.