We further note that the drafters of the Illinois Pattern Instructions recommended that no instructions be given on this subject concluding that it was argumentative, stated an obvious fact about human behavior and under many circumstances would lead to reversible error. See IPI No. 12.02 and Culp v. Olive, 45 Ill. App.2d 396, 195 N.E.2d 729. We do not entirely agree with the recommendation of the drafters of IPI and can visualize or hypothecate situations in which such instruction would be proper, but under the record in this case, even assuming the instruction should have been given, we find the error to be harmless.