Imparsimonious

On the evidence stated, it would seem imparsimonious to postulate such enduring continuants as psychoids.

While this model has some attractive features, it seems to me to give an account of the semantic-congruity effect that is, at the least, terribly imparsimonious.

This does not mean, however, that entirely new characters evolved each time the environment changed and placed new adaptive demands on the human organism—this would be extremely imparsimonious and inefficient.