Not churlish - maybe misguided ;-) I'm really not trying to suggest that distributed work is bad / evil / fails. Just that - all things being equal - colocated teams win. That there is a substantial body of evidence that not being colocated carries a substantial productivity hit.

My "gut feeling" is that regular funded sprint meetings plus remote working is an area of research that may well yield best long term trends. But wheres the proof :-)

Indeed! It's the complete absence of "distributed teams do X and Y better" research that I find fascinating. Unless it's hiding in a corner that I've not been able to find.