While it seems unlikely we can 'control' when we have an insight, it's now very clear that we can dramatically increase the likelihood that an insight emerges. The trouble is, we have to get used to letting our non-conscious brains do the work.
The human brain is an extraordinary information processing system. It is brilliant at executing certain tasks, particularly physical tasks that can be codified like playing an instrument or driving a car.
People who are praised for being smart "don't want to risk their newly minted genius status," and that fosters static, rigid organizations. Praise for effort keeps people engaged and willing to work hard.