Full frame CLEARY better than APS-C sensors (surprising to me at least)

You've made an interesting observation, and it would be enlightening to investigate it further.

There are solid, science-based reasons (re-hashed many times across many forums) why bigger sensors are better, all else being equal; but of course there are many other factors affecting the quality of a final print.

One problem I find with these forums is that, when an interesting point is raised, there are always people who rush to make unhelpful contributions, such as dismissing it with stupid one-liners or put-downs, possibly because they think it makes them sound knowledgeable. The resulting noise level makes interesting discussion very difficult. What we really need are a few interested parties who are available to attend the exhibition at the same time, who could then meet up afterwards in a more congenial venue than the internet to discuss the matter e.g. over a few beers. I would love to volunteer, but unfortunately I won't get the chance.  Without seeing it for myself, I certainly wouldn't dismiss what you say offhand.

Joe