from '79-'81 he was imo the perfect bass sound for the ABB as the '80s sound usurped most of rock music giving them a good taste of the old Berry flavor yet updated with his stylish Alembic perkiness which seemed to jell perfectly with the Toler / Betts era boys. but it's often said Gregg wasn't so thrilled and eventually wanted him out as some members continued a tumultuous path for many years of uneven releases. was it really Gregg vs David or were others involved in the unhappy marriage as well that caused further change, label pressure for hits, or just collateral damage from the tough times they faced internally and externally? for me there's far too few examples of the band in top form at that stage of their career to enjoy and David always excels.