Blank sheet and the "writer's block"
You see, the trouble is that when you're staring at the blank sheet, your mind is not clear. Quite the contrary, your mind is full of trouble and anxiety about you not getting anything done. Your mind is filled with negative thoughts about the situation.
If, instead, you just cleared your mind totally by concentrating (for example) on the blank sheet —in a meditative sense, if you know what I mean—, you'd do a lot better. After just, say, 20 minutes of good meditation, your mind would be ready for just about any possible battle. Writing would be easy, or at least easier.
Instead, after just a few minutes of staring and scribbling random words on the sheet, you probably just give up and start cleaning your apartment (or whatever it is that you do to avoid doing real work). After you've procrastinated for a while, you go back to the blank sheet and it's not a bit easier to start writing than the last time. It might even be worse.
So, the next time you're suffering from a "writer's block" and find yourself staring at a blank sheet, try to actually make use of the blank sheet and the power of a simple meditation.
(PS. I dislike the word "meditation" —maybe not for any good reason— but it's the best word for my purpose here. I would prefer an expression like not-thinking-about-anything-for-a-while, but that's not too illustrative either. The point is, if I've understood correctly, not to actively think about anything, but to concentrate on something meaningless, like your breathing, for example.)
[1] "Writer's block" is too fancy a name for the thing it is describing, anyhow.