DM-29615 originally disabled jointcal photometry in Gen3 only via the obs_subaru DRP pipeline definition. In the review it was quite reasonably suggested that we should disable this in the obs_subaru configs instead (which avoids a back-and-forther set-unset in config override and should turn it off in Gen2 as well as Gen3, which is good for consistency).

Unfortunately that got tricky (in the form of unexpected jointcal test failures), so I declared it out of scope and just left jointcal photometry enabled in the merged version of that ticket.

But it turns out that doesn't work, because of DM-29884. So on DM-29776 I'm going back to the original, Gen3-only DM-29615 solution, and on this ticket we can figure out how to replace that with a cleaner config-based solution.