One of the major problems of the $D$-$T$ fusion reaction is that it releases a 14MEV neutron. In large numbers, these neutrons irradiate the chamber walls and wreak havoc on the metallic lattice, introducing numerous technical problems.
What if we introduced a neutron poison into the plasma, such as Xe135 or B10, to capture these neutrons, rather than allowing them to slam into the chamber walls? The neutron poisons would be heated, and while it would be difficult to extract power from the heated neutron poisons, it seems more convenient than allowing for neutrons to destroy the tokamak.