Michlin recognise how much of a impact a story like that in the press would have so its less damaging to be seen to be doing the right thing than it is to do nothing.
As a note to compare on....fitted 2 pairs of avons this week...both had buldging ruber on the tread section that would cause instability at speed and were masivly out of balance.....this is a normal thing for avons lately so they obviously do have a problem but dont do anything about it, dont recall all affected tyres...
Just goes to show how differant companys deal with situations to keep their comapny profile in a good view.