What defects exist in the instruction that possession of stolen property tends to prove robbery rather than grand theft?

The first alleged defect that the instruction improperly informs the jury possession of stolen property may tend to prove robbery rather than theft was rejected by the state high court in People v. Lang (1989) 49 Cal.3d 991, 264 Cal.Rptr. 386, 782 P.2d 627. There, the jury was instructed that giving a false explanation for the possession of stolen property is a circumstance that may be considered with other evidence in deciding if the defendant is guilty of the offense charged, where the offense charged was robbery. (Id. at p. 1024 & fn. 16, 264 Cal.Rptr. 386, 782 P.2d 627.) The defendant argued the instruction was erroneous in permitting an inference that he was guilty of robbery rather than grand theft. The high court disagreed, explaining: "The instruction did not state that defendant's false statements supported an inference of guilt only as to the offense of robbery. The instruction was therefore a correct statement of law because, as defendant concedes, the false-statement evidence would support an inference of guilt as to either grand theft or robbery. Nothing in the instruction's language suggested it was intended to assist the jury in deciding which of these offenses defendant committed...." (Id. at p. 1024, 264 Cal.Rptr. 386, 782 P.2d 627.)