I'm going to make a wild guess here. It might be a reach. The essence of this contact is a 3-year deal with a team option on year 3. In others words, it's just a two-year contract because the Rockets will almost certainly decline the option. The 4th year "mutual" option was added as a face-saving measure by the agent to make it appear as 4yrs/$53M. Again, just my wild guess.
