Howie:
The answer is no and I've taken steps to avoid that possible incident. My davit crane is a custom build but the plan is to utilize the already mounted 900 lb. hand winch as the base point for one end of the line. From there, it goes out the boom of the davit, over one of two pulleys at the end and down to the load (snatch block) and back up to the boom, over the second pulley and down the boom to an electric hoist. That way if the hoist fails, I can simply lower the load by the hand winch at the other end of the line. All this, of course, has to be sized to the load you plan on lifting. If you don't trust a geared hand winch, there are heavy duty rack and pinion style hand winches that are slow to operate, but who cares if you only need to use it in an emergency.
Doing all this, I'll have less than 1300 bucks total in the building and assembly, 600 lb. working load rating with Amsteel 5400 lb. line.