otherwise we wouldn't be having this debate. Nothing seems to be simply explained about this occurrence, without having to expound on theoretical possibilities.

The one thing that has been brought up many times before that may be a big factor; the angreal that Moiraine left on the wagon for Lanfear to use. We know Moiraine saw it in her visions, and we know she didn't like something about it, yet, she went out of her way to make sure it was there so the vision would come true. It just seems to me that the angreal played a factor somehow, otherwise it could have stayed in the sack of odds-and-ends she dug it out of and everything would have turned out pretty much the same. For those that have forgotten, here's Mo's pov about the angreal:

Moiraine did not like that circle of carved age-dark ivory. At first glance it seemed to be an acrobat bending backwards to grip his ankles. Only a closer look would show that his wrists and ankles were bound together. She did not like it, but she had brought it out of Rhuidean. Yesterday she had taken the bracelet from a sack of odds-and-ends and left it lying there at the foot of the doorframe.

For my money, I still think the angreal has some sort of binding property. It enhances your power, but it also binds a part of your power into the angreal somehow, making you susceptible to being dependent on it forever. If it falls into someone else's possession, they gain your lost strength. (Something along those lines, anyway.) At the least, there seems to be some evil association with the thing, otherwise I don't see a reason Moiraine would have disliked it, and could have used it herself.