Stephanie Goldman gave the critique at the NCSFA meeting. She kept stressing drawing from life, "to expand your memory bank". She could tell which paintings were painted from life by the absence of camera colors. I have never attended a critique like that before, it was quite interesting AND educational.
When I draw from photos I feel I am "cheating" even though I only use my own photos. I agree with the memory bank thing. I have always tried to make compositions on my sketchbook pages but as always the subject moves, or something moves in front of it. Why not use my memory bank to finish the darn thing? Just make something up.