I was taking the quote to mean that not many people were researching causes/treatments of Alzheimer's that were not related to the "Amyloid hypothesis."
If I am misinterpreting that, then it is my poor reading. (I have some excuses right now, but they would be just that. :) )
Certainly fair. I've just taken, quite heavily lately, to the principal of charity.
To that end, the most upvoted direct response to you is a better worded version of what I was getting at. Sunken costs and changing where you are spending your money is my speculation on why things went the way they did. I don't have a solid answer for why this is so, though. At least, not one that generalizes.
To repeat what I think was the heart of your initial question: Why do people form strong beliefs? That is a very good question that I don't think anyone has a solid answer on. Just more beliefs that have strong proponents. :)
If I am misinterpreting that, then it is my poor reading. (I have some excuses right now, but they would be just that. :) )