Great sketches!!! My sketching skill has totally gone down the drain since I started sculpting :/ don't know whats the connection but good sketches now come like hiccups and are occasional event lol :/
Aw, that is a shame. Maybe you're doing a cubist sketch, trying to include parts you'd expect to see if you were able to view the piece all at once? I've noticed my interpretation of space is a little different since sculpting more.