It would also make it more difficult to detect fraud.
Quite the contrary - Input liquid water at 'x' flow rate goes through the E-Cat manifold, exits at the SAME flow rate (unless you are dumping water somewhere); now simply measure the change in temperature, let's call that Delta T. You know the flow rate, you know the input temperature, you know the output temperature - look up the Enthalapy values and badda-bing - you have your answer. http://www.engineeringtoolbox.com/heat-work-energy-d_292.html