Supercurrent dissipation and strain-induced damage in (Bi, Pb)2Sr2Ca2Cu3O10/Ag high-temperature superconductor composite tape, at 77 K in self-field, are studied by I–V curve analysis. Five dissipation models are considered, and differently processed tapes are compared. After making self-field corrections, which are normally ignored but we find essential to do, collective flux creep stands out as the only dissipation mechanism which explains the data. Confidence in the analysis comes not only from the goodness of fit, but also from experimental confirmation of two fitted parameters. The identification of the main dissipation mechanism has great practical value, because it enables definitive tape characterization, based on intrinsic physical properties.