good points made ... but I see no problem with them.
pairing people up is probably a good idea.
the main problem appears to be the "conventional wisdom" that adding extra people as the search progresses is not worth the problems and difficulties. I can see why SAR teams have come to believe this. But by the same token, there are ways that things could be kept flexible if good comms are maintained with team members (incl. regular comms checks), and someone updates the overall navigational map (who-is-where). GPS systems and mobile radios have made this more practical.

we're looking at moving into an era of decreasing resources and budgets. creative solutions are needed, or lower success rates will need to be accepted. just my $0.02.

Pete