All rather amusing.....at the risk of sounding somewhat jaundiced...
having been on the wrong end of management/union negotiations myself in the past and having put all my eggs in the union basket only to find I had completely wasted my time and effort with the union rolling over, I did the decent thing for my self esteem and T&C's, I left.
I don't suppose for one minute any of our BA contributors feel quite that much conviction about the anti OS cause.