  We develop an impact representation for the generalized distribution
amplitude which describes the exclusive hadronization of a quark-antiquark pair
to a pair of mesons. Experiments such as gamma^* gamma -> pi pi and gamma^* N
-> pi pi N' are shown to probe the transverse size of the hadronization region
of the quark antiquark pair that one can interpret as the transverse overlap of
the two emerging mesons. An astonishing feature of this description is that low
energy pi pi phase shift analysis can be used for understanding some properties
of quark hadronization process.
