Hyperon decays, EMC results and the spin structure of the proton

A new approach with a flavor-SU(3) classification only for the weak currents and not for hadron wavefunctions shows that hyperon decay data are essentially useless and do not give model-independent information about proton spin distributions. However, analysis of weak decays and polarized EMC data using SU(6) without hyperon decay data confirms previous conclusions and show them to be insensitive to SU(6) symmetry breaking. Errors introduced in previous analyses by use of hyperon data and SU(3) are down in the noise. This conclusion is verified in two models for SU(6) symmetry breaking by a polarized sea.