Pion-photoproduction data is examined to check for the nucleon-helicity
conservation predicted by asymptotic QCD. The differential cross section shows
agreement with constituent-counting rules, and polarization data is not in
disagreement with conservation of nucleon helicity. However large uncertainties
in the polarization measurements do not allow a conclusive statement. The
helicity amplitudes from a partial-wave analysis are also examined for helicity
conservation. While the amplitudes become small as s increases, the s
dependence of the helicity-conserving amplitudes is similar to the dependence
of the non-conserving amplitudes.Comment: plain tex, 6 pages, 8 figure