Electrochemical response (insertion isotherms or capacitances) of disordered host matrices (porous, amorphous, i.e., conductive polymers) under different kind guest-induced deformation mechanisms is studied. The deformation is translated into a change in the distribution of the host site energies as a function of the applied potential or the concentration of the guest species. It is shown that the insertion-induced transformations of the host matrices are well detectable in the form of characteristic peaks, minima and plateaus appearing in the capacitance curves. The role of these features in the characterization of the matrix statistics and the guest thermodynamics is discussed.