I have seen people with this condition, and there are some extreme cases where the difference between one eye and the other one is extreme.
I didn't know Ryan Gosling had one lazy eye, but in that picture we can indeed notice a slight difference.
And the eyepatch seems like a simple way to threat this condition, unlike eye surgery which is surely be one of the most uncomfortable things we can experience.
RE: Let's talk about STRABISMUS [The medical term we popularly know as half past four]