I think we all get cob webs in our brain from time to time, whether it's from not training for a while or training too often. I have found, as I am sure most have, that training hard and often tends to shake these webs loose. Problem is, every so often, these webs clog up the brain drain and it's basically the same effect as before, but more frustrating. Taking a step back from training and letting the drain clear will give clarity to our endeavours. Letting us progress and move forward once again in our training.
Recently I had to step back and take a week away from rolling and sparring, let the cob webs fogging up my brain wash away. This has been the case on more than one occasion, and often it leads to a spike in progress.
Moral of the story, sometimes you need a break from training to help refocus. Take a step back, clear your mind, and return reinvigorated.