But those B737s (eg, 800, NG) that were fitted with the after-market mod Scimitar installation (without beefing up the wing attach load path design) would necessarily suffer a reduced wing attachment fatigue life due to the higher loads imposed by the addition of the Split Scimitar winglets.
Perhaps more engineering learned members than I might like to comment?
excellent point- unfortunately there are probably very few if any of the old beards left who would know for sure
I do know that one of the arguments re winglets for the first NG types was just that- increased bending loads. While one could assume that was properly taken care of- the viral infection of the MDC types in the aero design groups coupled with the cheaper-faster- mantra may well have overlooked that issue.
It remains to be seen just where the cracks were found.