Nope, not in my pocket!
There must be lots of better choices for a pocket gun. There couldn't be too many that would be worse! Some of the problems I would have carrying a 44 mag derringer might be: Controlability, Safety, Accuracy, slow to get into action, even slower for the second shot, limited firepower, and concealability. Those things are not small, a J frame would be better in every respect.
Stay Safe,
Savage