Since the sexual-abuse scandal involving Roman Catholic priests broke more than four years ago, thousands of lawsuits against clergy and dioceses in cities across the country have been tried or settled for an estimated total of $1.5 billion. But more than 700 such cases filed against the dioceses in San Diego (160) and Los Angeles (560) have languished since 2003. This is by far the largest collection of priest-abuse cases anywhere. Attorneys representing adults who say they were molested decades ago as children argue there is a simple reason that none of the cases has gone to trial: Church officials here and in Los Angeles have been masters at stalling. In language dry as talcum powder, an appeals court last week seemed to agree. "We will not delay this matter yet again, in regard to what we believe is a peripheral issue having no bearing on defendants' ability to determine the merits of the actions," judges of the 2nd District Court of Appeal in Los Angeles said in dismissing the latest action from diocese lawyers.