This manor of practice emphasized speed and power, Oyata's instruction didn't. Though important, they held less relevance in his methodology. Sparring asserted that those traits could (or should) assure one's ability to triumph in a confrontational situation. In fact, this manner of practice instilled more bad habits than usable traits.
With the included “padding”, strikes that would (normally) produce cumulative (if not immediate) effects, became pointless to even attempt. Those strikes that were less effective (in an actual confrontation) were commonly implemented in the “sparring” arena. Though commonly argued that sparring is the “closest” way to practice for a confrontation, it is (actually) the best way to instill bad (ie. Non-productive) habits (at least when compared to Oyata's normal training methodology).
After the mid-eighty's, sparring was never addressed (at his dojo, nor in the Yudansha classes that he taught). It was Oyata that initially emphasized the inherent drawbacks to participation in this practice.