Working Together in principle is a good idea. The intention is that it avoids the old fashioned butting of heads that Management v Union meetings were... By being fully involved in the process, union reps are ready to buy into the result, rather than wait for a management plan to be presented then just say "no"
On the current pension example... It's difficult. I know and have worked for over a decade with some of those reps who have been involved in this process. I know with certainty the level of integrity and deep-rooted union beliefs that those I know have. I am sure that, if they have accepted this deal, its because they considered it the best option available.
However, I am still not happy that they went down this path in the first place. Union reps are just that - representatives. Their authority is based on the approval of members. By entering in to confidential negotiations where they were not able to consult with members on their path, they have over-stepped their authority in my view.
Realistically there may be no alternative to this plan... I will wait and see... but, if we back down and accept this deal then I think the TUs can just pack up and go home. All authority and influence in future negotiations will be lost.
I hate to say 'I told you so' but I voiced by concerns over the path they took right at the outset.... I told you so.