Re bending moments, I know the DC8-61 & 63 series would bend - suspect same with all types, save perhaps the 747 simply due mass and oblong cross-section.
If I may be permitted to wander a bit with some off-the-cuff thoughts...
Agree on the fbw notion - once it "gets there" it springs loose, so to speak? In assessing all this and as a pilot of these things I place a huge amount of faith/trust in the design/certification/manufacture process in the sense that I ask no questions of the airframe or systems. I take "what is" from where I sit and if it disappoints, that is the designer's/regulator's problem. Essentially, none of us are trained test pilots, having no business outside the normal flight regime, (save circumstance, obviously), and so that is the only approach open to professional airline pilots today. We used to do nuts-and-bolts courses, drawing systems, sometimes playing "what-if" across the Atlantic; no longer. Second-guessing the airplane and it's designers is not possible from our cockpits and we have to accept that both the manufacturer and the regulator have done their work correctly. In my experience, I have yet to be surprised, have yet to find an ECAM drill poorly thought out, so I guess they've done okay.
That's why this accident is truly an enigma. I suspect there are many A330 pilots here, silent or otherwise, who have been in the very same circumstances as this crew and are really, really wondering what unfolded so swiftly as to bring the aircraft down. We can all imagine different scenarios, (and have posited them here) but in the end all we know is it took off and it crashed just about 4hrs later.