Growing potatoes from true seed gives more genetic diversity to allow at least some plants to survive under a range of conditions (wet/dry, hot/cold, etc.), but genetically uniform, asexually-produced plants will have higher yields in an environment to which they are all well adapted.
Work Step by Step
To get to this answer, reread the chapter on the value of self-incompatibility, and also review earlier chapters on the value of genetic uniformity in stable habitats. This points to the trade-off between the two ways of producing potatoes described in the question.