The lesson I'm hinting at is larger than Rome: examine any legend of innovation, from inventors to scientists to engineers, and you'll find similar natural omissions by history. History can't give attention to what's been lost, hidden, or deliberately buried; it is mostly a telling of success, not the partial failures that enable success. Without at least imagining the missing dimensions in the stories, our view of how to make things happen in the present is seriously compromised.From Scott Berkun's book The Myths of Innovation
I think daydreaming is a distinctive mode of cognition especially well suited to the complex, 'fuzzy' problems that characterize a more turbulent business environment. ... Daydreaming is an effective way of coping with complexity. When a problem has a high degree of complexity, the level of detail can be overwhelming. The more one focuses on the details, the more one risks being lost in them. ... Every child knows how to daydream. But many, perhaps most, lose the capacity as they grow up. ...From Dov Frohman - Leadership the Hard Way
Imagining = daydreaming!
Yes, you now have a good reason to daydream. Not that you can do it all day but it is allowed and should be granted a reasonable amount of time.
How much is reasonable?
That depends upon the kind of fuzzy logic problem you are attempting to solve.
Do you have a time to daydream in your day?