I would have to agree with your assessment, ChickenHouse. Someone - my guess, a team of someones, with many tech. manuals available to them - spent months if not years preparing for this.
If evidence magically comes to light conclusively implicating either of the pilots as a spur of the moment suicide, I'm firmly donning my alfoil hat and joining the conspiracy theorists - i.e., I will not believe it. If one of the pilots was involved, (and I don't believe this to be so for one moment), it was as part of a highly specialised team with a clear agenda, and NOT a spur of the moment suicide.