I'm still going through this report posted on 11/24 from the California ISO Market Monitor regarding the causes of the August outages and resulting market effects, but one item in particular caught my attention, see below. I place this observation in the category of "Practice trumping theory"
The CAISO market was structurally uncompetitive during the high load days in August. Although prices were very high during the high load days in August, analysis using the CAISO’s day-ahead market software indicates that system wide mitigation of imports and gas-fired resources during this period would not have lowered prices. This reflects the fact that gas-fired and other resources that may be subject to mitigation were generally infra-marginal in re-runs of the day-ahead market using cost-based bids, and that high prices were set by demand response and other resources not subject to mitigation.