I hadn't thought about the idea that keeping people from getting good jobs makes them less likely to find good association outside the cult, but that makes perfect sense. I've seen it in my wife too - when she worked it was always around uneducated people and most of them were lazy and directionless and it's easy to get the idea that "this is just how worldly people are."
There are many reasons for the anti-education position WT holds to. I agree 100% with the statement made above.
Learning to think critically is only part of the equation. A person who is college material likely has that worked out anyway before they even go. As an ex that went to college during my JW days, I also know that going does not automatically make someone wake up and leave. It took 11 years after graduation for me to finally leave. Many JWs have gone to college and remained in the organization for many years afterword. What really contributed to my eventual leaving was realizing that my success was independent of anything having to do with the JWs, and that the organization was responsible for any major failures I had in life.
A very key part of the equation is success itself. Successful people do not make good robots. Successful people generally do not struggle with the same financial issues, and other higher order issues caused by financial stress, (such as marital issues). Successful people don't need their egos constantly validated by peers, and certainly not of those who are less successful. Successful people do make good friends with others who are generally equally educated, and successful. They also learn much from this socialization.
In short educated = successful, and successful people by and large do not make good JWs.
d4g