Has the E791 experiment measured the pion wave function profile?

The cross section of hard diffractive dissociation of the pion into two jets is calculated. It is obtained that the distribution of longitudinal momenta for jets is not simply proportional to the profile of the pion wave function, but depends on it in a complicated way. In particular, it is shown that, under the conditions of the E791 experiment, the momentum distribution of jets is similar in its shape for the asymptotic and CZ wave functions, and even the ratio of the differential cross sections is not far from unity. We argue therefore that, unfortunately, the E791 experiment has not yet measured the profile of the pion wave function. For this, the experimental accuracy has to be increased essentially.