Before revision:  While both these policies are optimal  , we show that they are equivalent with respect to the expected distance traveled by a request (request distance), although MTR tends to be fairer, i. e., has low variance.
After revision:  While both these policies are optimal among all unidirectional policies , we show that they are equivalent with respect to the expected distance traveled by a request (request distance), although MTR tends to be fairer, i. e., has low variance.