  The detection of gravitational waves based on the geodesic deviation equation
is discussed. In particular, it is shown that the only non-vanishing components
of the wave field in the conventional traceless-transverse gauge in linearized
general relativity do not enter the geodesic deviation equation, and therefore,
apparently, no effect is predicted by that equation in that specific gauge. The
reason is traced back to the fact that the geodesic deviation equation is
written in terms of a coordinate distance, which is not a directly measurable
quantity. On the other hand, in the proper Lorentz frame of the detector, the
conventional result described in standard textbooks holds.
