This is an interesting case study. Martin put $5k at risk on a very conservative goal — spending at least 8 hours a week on a house renovation project for a total of 249 hours by May 5. He actually signed the contract on Oct 21, right before he started shooting up above his yellow brick road. He maintained a blazing pace until the holidays. Then sometime in January he hit the 249 hours, making his $5k safe, and you can see what happened to his productivity since then:

I’d say it’s time for a new commitment contract!