oh yes, I often think that those greats who left so much of their work undeveloped were on to something : like presents, they are in a way spoiled by the opening.
When I feel like this (often) I look at other stuff for a while, drawings mostly. Films.
I do wonder sometimes, looking at the photos I take more so than anything, whether the internet tends toward minimising the differences in work? At school I remember being quite satisfied with the direction my sketch book was taking, and then looking at someone else's, someone better, and allowing what they did to somehow feed in to what I was doing....only in a weaker, paler way. It never helped and made me feel dissatisfied. Which makes sense really, as if we were all doing that all the time then eventually the whole class would be a vapid, watercolour wash out of what the individuals might have been. That's not to say that other people's work is not an inspiration but it ought not be so direct, and that perhaps the internet is to my mind subtly the same as that classroom, just on a grander scale?