Did you see that he included the numbers to answer your questions in his comment? An 80% gain in annual job utility, lasting four years, with a 50% chance to ac

Did you see that he included the numbers to answer your questions in his comment? An 80% gain in annual job utility, lasting four years, with a 50% chance to achieve the gain for each two month period during which he experiences a 60% utility lost. Using those numbers, it would be worth doing at least a few of these trials and it would be very unlikely to have to do more than that (especially if his skill is increasing during the trial periods.)