I have just listened to the BBC interview of a person from INMARSAT. If I understood correctly
1) they did create and provide a model of the likely "disappearance" zone about a week ago i.e. over a week after the event, based on analysis of pings and modelling of typical MH flights. Congratulations for the initiative to what is in principle a data-transmission organisation.
2) as search organisations did then go to the area, it is also logical that the Malaysians would want to also remain focussed on other scenarios until they had been rendered impossible. Had they not done so and had the Inmarsat model have subsequently been proved wrong would have been unfortunate.
If I add to that
3) as far as I have been able to ascertain, there is no firm evidence of what happened inside the plane after the last voice exchange
4) likewise there is little evidence of where it actually then flew and even less on how it got onto the track it seems to have followed, or for that matter any other possible tracks
I find the statement emanating from the Beijing family group very unfortunate and possibly due to a lack of counselling and understanding of the bigger picture. It is imperative that the industry works to communicate on why it takes time and thus avoid such happenings. That said, I have to admit that the comment of the Inmarsat responsible that, by obligation, ships are tracked every 6 hours and that a similar tracking could be instituted for aircraft blew me over, not by its simplicity, but by the fact that say ICAO has not mandated it. I hope they will see the value. We don't need another one like this.