Perhaps I can give a perspective from the oil operators side of things.
They have to commit to an ability to rescue a helicopter load from at least the 500m zone around the installations.
So circa 20 people. They have to be retrieved within 2 hours (beyond that survival is questionable). Now given the Jigsaw project - no local standby vessels and a scenario where people are dispersed in the water, the only way to retrieve them within that time period is to have WWPLBs on every person.
This incident shows the whole process was not well thought though. Inspite of conditions being reasonably good (apart from visibility) the first recovery occured over 1 hour after the ditching. As everyone was in the rafts, no real problem apart from hypothermia affecting a few survivors. The ARRC (surface rescue craft) arrived just within the 2 hour period and the BP management could announce a success for Jigsaw.
Now we know that given intelligent beacons it cannot work. Given 'dumb' beacons the original Jigsaw trials are probably OK. So long as everyone practises regularly - because reputedly it took a lot of practice for the trials crew to meet that performance standard - 20 people within 2 hours, dispersed at sea, to be winched to safety.
But in real terms the people who need a priority rescue have the PLBs with the weakest signals. Until the strong signals are eliminated then their recovery is unlikely to be possible.
And all this ignores the issues about the aircrew not knowing how to operate the ELT!!!!