[notahacker]

Yep. I'd say the way forward for testing is the freighter, which doesn't have evacuation issues, doesn't unload at passenger airbridges and (if packed properly) doesn't have the same sensitivity to rolling motions.

But freighters generally have lower utilization on less price-sensitive routes, so operators tend not to care so much about fuel economy (and for related reasons, usually aren't new aircraft). So however much easier the route to certification might be, it's a horrible market...