I think the initial answer has to be that there are many here who haven't a clue what you are actually suggesting in detail. I have not spotted any posting spelling it out. (Give post number if I'm wrong) It sounds much more complicated that the UU rights issue and very few understood that.
The second answer is that many would suspect it to be just another ploy letting the MMs get out of jail free.
The third answer is that the MMs are fearful of what it might cost.
The fourth, FSA and LSE are still looking for a better cover-up and like the ostriches referred to earlier dont want to put their heads up
Fifth, There really are some who want it to go to court.