I know about the clocking thingy. I even use it to make 4 storms events to create the debris for my builder......but after clearing debris from the 4 storms,he is still not a master......I gave up and started afresh......

...When they become a master at somthing there gaining at somthing decreases so it was better that you started over but just renember to have a master builder when tour at that point in the game