Often when there is question with complex/long code do develop/tweak/adjust, there is situation where few experts are involved and then the possible solutions are posted in few seconds and then the first solution is accepted and the others are unfairly left out and their work is not appreciated.
I think the option where you will have the button for experts to "say" that they are "commit-ed" to question which will imply to other experts looking at same question that there is someone working on possible solution and after the solution have been posted the commit notification will be lifted so that eventually other experts can contribute.
This option does not need to be exclusive other experts can post to this question but it will give hint that there is someone working on it and that the free experts can look at other questions...
Expert Comment
No, I don't think that is really what the overriding goal should be, or has been. That's too focused.
The overriding goal is (or should be) to provide the best experience possible to the EE community, to keep them engaged in using the site and contributing (while successfully keeping the lights on and servers running). There is recognition that every contributor (Asker or Answer) has his or her own motivation for supplying the content and efforts that they do. Those motivations have a broad scope. Some are synergistic, some are complementary, some are competing and some are antagonistic. The goal is to successfully keep the creation of good content coming.
Answers are commoditized. You can find those on many, many sites. The key differentiator at EE is that you connect to a community that is quite good at supplying answers. The community cannot be commoditized. It has been, needs to be, and will continue to be nurtured.
At some points in time more successfully than others :)