In Bret Harte Inn, Inc. v. City and County of San Francisco (1976) 16 Cal.3d 14, the Supreme Court traced the recent development of the law applicable to proceedings for challenging assessments and discerned an abandonment of the former drastic test which courts had applied, to wit, whether an assessment practice constituted an arbitrary and wilful disregard of the law and whether such practice amounted to a constructive fraud on the taxpayer. Judicial review now entails a search for "arbitrariness, abuse of discretion or failure to follow standards prescribed by the Legislature." ". . . Recent cases have also distinguished between challenges to the result reached by the assessor after applying a sound valuation method and challenges to the validity of the method itself." (Bret Harte Inn, Inc. v. City and County of San Francisco, supra, at p. 23.)