The answer to the original question is we should not use vertical speed as in that mode it is possible to fly AWAY from the selected altitude.
Using that logic, we should not use pilots, either!
AFAIK, the pilot still initiates climbs and descents by setting up the MCP, FMS, throttles, and other controls, then either hand-flies the airplane or monitors the autopilot. To disallow use of an automatic or semi-automatic function because it is not idiot-proof is patently ridiculous.
