It is of course possible that winds in the middle of the gulf, where MH370 vanished, are different, but my guesstimate for the area is for light to medium winds from the E-S sector. Which would have kept any debris from an in-flight breakup in a reasonable area, and pushed any debris and oil on the surface in the direction NW-N.
Perhaps someone can dig out some upper level wind charts from the area for the last two days. This might help in guesstimating the debris spread from any in-flight breakup at cruise level.
The last point of contact with the aircraft might not be the point of break up, if indeed that happened..... It may have travelled 90 degrees to the last known direction whilst/if the crew had time and attempted a recovery... That was part of the issue with AF447... It had turned 180 degrees from the original track by the time it hit the water, i understand