/ic/ - Artwork/Critique

What's the point of exercising gestures as a beginner? I know they're great for understanding rhythm, how the human body works in various positions, and synthesis, but it seems to me that without profound knowledge of anatomy it really is just incredibly stressing.

Like, how do i know WHICH lines to draw when doing a gesture in like 1 minute? I usually try to start with the head and search for a line that synthetizes the torso and balancing leg, and it's easy to find it only in very dynamic poses.
Arms and legs however i'm not finding out how to synthetize without just drawing the contour.
Also, they all look so incredibly one dimensional. Are my lines supposed to ALSO describe the tridimensionality of the form or do i dedicate other lines (like, quick circles in strategic places like the belly) for that?
And am i supposed to draw blind? It's really hard to not look at the paper for most of the time when you have such little time.

Pic very related, these are all one minute gestures i just made. I always do a lot of them, but I hate how they look, how can i get better at this? Should i completely ditch them and concentrate on anatomy and deeper understanding of perspective?