Maybe Ciaran's views reflect his background. He previously worked for the Federated Union of Employers. If the executive, who were deciding strategy, believed the 'new realist' nonsense about strikes no longer being effective it is hardly surprising they didn't come up with ways of winning the strike. It did, the problem being that it was favourable to the banks. The executive believed that public opinion could win the dispute for them and that the government and its agencies would take a neutral position.
Public opinion is a great aid in any dispute, it raises morale and can be of concrete use.
However it does not, on its own, force the bosses to give in. Despite having the public, media figures, and clergy on their side they were outside the door for 18 months and ended up going back with only a partial victory. The bank strike was winnable. Pickets went on to every branch. Where scabs were going in there should have been large and loud pickets to let them know this was unacceptable and would remembered long after the strike was over.