I have noticed that over the course of the last twelve years, my ability to handhold my camera steadily at slower speeds has come and gone in cycles, without any apparent logic behind the changes. Sometimes I can handhold at 1/4s with a 50mm lens no prob, and other times I'll find bad camera movement at 1/30s when I was actually trying to hold the camera still. Hell, I used to shoot an RB67 handheld at 1/8-1/2s regularly with good results.
So what I'm wondering is if anyone knows of any exercises or drills one can do to help maintain more consistently steady hands. Please don't suggest a tripod or monopod, as that's not what I'm asking. Any thoughts?