How has section 667.6, subdivision (d) of the California Criminal Code been interpreted in the context of sexual assault cases?

In People v. Senior (1995) 33 Cal.App.4th 531 (Senior), the defendant was convicted of multiple sex-related offenses. He received a lengthy prison sentence, which included five consecutive three-year terms under section 667.6, subdivision (d). (Senior, supra, at p. 533.) The matter was remanded twice, and both times the trial court reduced appellant's sentence, but it did not alter the terms under section 667.6, subdivision (d). (Senior, supra, at pp. 533-534.) In his third appeal, the defendant raised a challenge for the first time to the sentence based on section 667.6, subdivision (d). (Senior, supra, at p. 534.) The Senior court determined (1) this issue had been ripe for adjudication in the previous appeal; (2) there has been no significant change in the underlying facts or applicable law; and (3) the defendant has offered no reasonable justification for the delay. (Id. at p. 538.) The appellate court deemed the claim to be waived. (Ibid.)