Originally I thought of Vaccine Passports as an excellent, obvious proposal, (as I gather do most of the public), but an idea which unites opponents Iain Duncan Smith and Jeremy Corbyn raises issues which must be looked at seriously.
The pros and cons are based on very different starting points, but I think the any questions panel (BBC Radio 4, 2.4.21)) gave contradictory answers to the first and penultimate questions (which starts 29 minutes 40 seconds into the programme). Only the later question was directly on the question of Passports.
So rather than choose between them, I refer readers to Any Questions. My real concern is the tendency of many, quite intelligent people, to give more importance to short term consequences rather than long term, which is quite important on the big issue of threats to the ecosphere.