Malaysians saving face?
Having worked in Singapore/Malaysia for nearly 20 years, I don't believe this stuff about the Malaysians 'covering up' what they know for days, just to save face. They're pretty clued up at senior levels (even if performances at press conferences are not very impressive). They're not stupid enough to think that with ships, aircraft and miscellaneous technically expert personnel of sundry countries running around the search area(s), monitoring every bit of equipment they can lay hands on, they would be able to cover up anything really significant for any time. 'Face' is important in this part of the world, but not to such a lunatic extent. Seems much more likely that they've been working with unconfirmed information, and pending confirmation they've been hedging their bets as to search locations. Isn't that what anyone sensible would do? For all we know they have been sharing unconfirmed information with their international collaborators in the search effort.
Similarly with the passports. They didn't release information publicly until they had something solid to release (and until they had spoken in Frankfurt to the mother of that poor chap, not least). Fair enough, it seems to me.