How have courts interpreted flight instruction in a hit-and-run case?

In this case, it is undisputed that there was a hit-and-run accident, that someone was injured, and that the driver was under the influence of alcohol. "The sole contention made by the defendant was that he was not the perpetrator. Thus, the question left for the jury to decide was whether the defendant was the perpetrator of the crime. Once the jury found the defendant was the perpetrator, the case against him ended for all practical purposes. The only factual issue was the identity of the perpetrator who fled the scene. The flight instruction added nothing to this determination.... The court erred in the instant case by giving the flight instruction." (People v. Parrish (1986) 185 Cal.App.3d 942, 948, 230 Cal.Rptr. 118.)