What could possibly be the excuse in a criminal investigation to delay attempts to extract valuable data from the recorders by more than a month, if it is correct that the recorders will not be sent to Honeywell until the first week of January?
Absolutely none, you're quite correct. Safety is of
immediate concern, whether proving there's no issue or uncovering same if there
is one, while legal issues can take
years to resolve (think Habsheim, Mont St.-Odile, Lockerbie etc). The two are incompatible but it serves French-government (ie Airbus-stakeholder) interests to use the latter as an excuse for keeping the lid on in the former.
On a related French-aerospace legal issue, think also how long it's taking for the legal cases against former and current Airbus employees accused of corruption in the 2005/6 A380 shares fiasco. And stepping outside aerospace for a second but staying in France, there's a long-running legal case against former-president Chirac which is going nowhere fast while corruption charges against former-prime minister de Villepin are not rushign through the courts either.
But French legal matters only proceed at the pace the current French government dictates -- the two are inseparable. This fact is of considerable relevance here re the A320 loss.
And it will get worse from a transparency point of view from 2009 as the French 'reorganise' EADS and Airbus, bringing the latter more under French law...