I think that there is a way to study too much so that you really don't retain any of the information that you've been looking at. You definitely do need to study, but it works much better if you study a litle bit every day and not all at once.
It is possible to not retain much information because you are overloaded and you are not committing the information to long term memory. There are different ways to study and if you are just reading the same thing over and over it may not help you remember the information later.
Everybody tries to find solutions for work that involves...not working. There is no solution for hard work and repetition, regardless of the system people claim to have developed. While advances in neural implants might make not studying possible one day, its in the future. Today, the only real way to study is the old fashion way.
While there is a limit to how much information somebody can retain in a given time frame, that doesn't mean that excessive study completely negates what is being studied. Some things are still being picked up and held onto by the brain, so there's still studying and the result of it taking place.
I do not think it is possible to study so often that you never actually study. I think that would be nearly impossible to do. If you are reading the material and trying your best to learn it than you will pick up the knowledge regardless of how often you study.