What is the effect of instructing a jury to disregard the "ultimate fact" in their consideration?

[859 P.2d 707] Such an instruction removes the "ultimate fact" from the jury's consideration without leaving behind any "predicate facts" to be found. If a mandatory irrebuttable presumption "tend[s] to deter a jury from considering any evidence for the presumed fact beyond the predicate evidence" (Yates v. Evatt, supra, 500 U.S. at p. ----, fn. 10, 111 S.Ct. at p. 1894, fn. 10), an omission, by definition, withdraws the omitted fact entirely.