I Always measure the load across the t-STAT to set the anticipator. we would wrap our ammeter with 10 winds of wire and run it in series with ourstat wire. this does the actual reading. (My ammeter wouldn't read below 1 amp so the ten wraps make it readable then divide by ten.
ex: 4amps/10 = .4 anticipator setting.
THis has always been the most accurate way I know