In his article An Essay on the Quieting of Products Liability Law, 105 Cornell Law Review 101 (2020), Aaron D Twerski, one of the reporters of the Restatement (Third) of Torts: Products Liability, compares the difference between the risk-utility test applied in most states (which relies on having the plaintiff prove a "reasonable alternative design (RAD)") and the consumer expectations test followed in 17 jurisdictions to determine if a product has a design defect. He concludes that, regardless of the approach used, the vast majority of cases include proof of a RAD.
Twerski theorizes that using proof of a RAD: 1) tells “a far more compelling story” than consumer expectations; 2) relates to fault which, in turn, leads to higher damage awards; 3) may be needed as a substitute if a judge denies a “consumer expectations” instruction, and 4) supports the claim that a product disappoints consumer expectations.