thanks for the comments
i like poses in the 10 minute range... over that and i'll only enjoy it if i have a good drawing to work with, which unfortunately doesn't happen as much as i'd like. less than 5 and i feel like i haven't shown enough... i work better slowly than quickly (although 5-10 minutes isn't exactely slow i guess... animation training makes you quick).
i work standing at an easel whenever possible. the double use drawing horses for sitting or standing doesn't work for me, i like being able to stand and have the drawing and the model almost directly side by side. my technique is hard to explain, but it involves lots of use of the pastel, a tissue for smudging, and an eraser. i often draw with the eraser as much as with the pastel, soemtimes smudging a whole drawing into a grey tone and pulling out lights, smudging, knocking in darks, pulling out more lights, smudging, ect... on a 20 minute pose i may have smudged the drawing 20 times. working with broad chalk strokes and an eraser is more of a painterly approach and i enjoy it more.
the act of 'smudging' was frowned upon so much by instructors and other artists as i've studied over the years. know i look back and realize they didn't know what the hell they were talking about, it works for me