[en] Several rotational structures have been identified in ¹⁷²Ta. The doubly decoupled π1/2^-[541]xν1/2^-[521] band has been followed beyond the first backbend and a crossing frequency has been extracted which is almost the average between the values found for the participating orbitals in neighboring odd mass nuclei. Striking additivity properties concerning both deviations of inertia parameters and alignments are shown to be a systematic feature of these structures. These results may be at variance with earlier assertions on the deformation driving tendency of the πh_9/2 orbital and with the exclusive νi²_13/2 character of the first band crossing. (orig.)