Even though humans recognise objects as shapes gesture and shape, and also most forms have pretty much the same shape from 70% of angles. You can build the form out of good looking shapes, but form-first usually makes ugly looking pictures because the shapes aren't being considered. Shouldn't art students really be learning shapes first? Especially for anatomy. Trying to make all the forms right is such a trap for not progressing when you could be working on shape design. Just a thought for the crabs.