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We revisit the observed correlation between Hbeta and FeII velocities forType II-P supernovae (SNe~II-P) using 28 optical spectra of 13 SNe II-P anddemonstrate that it is well modeled by a linear relation with a dispersion ofabout 300 km/s. Using this correlation, we reanalyze the publicly availablesample of SNe II-P compiled by D'Andrea et al. and find a Hubble diagram withan intrinsic scatter of 11% in distance, which is nearly as tight as thatmeasured before their sample is added to the existing set. The larger scatterreported in their work is found to be systematic, and most of it can bealleviated by measuring Hbeta rather than FeII velocities, due to the lowsignal-to-noise ratios and early epochs at which many of the optical spectrawere obtained. Their sample, while supporting the mounting evidence that SNeII-P are good cosmic rulers, is biased toward intrinsically brighter objectsand is not a suitable set to improve upon SN II-P correlation parameters. Thiswill await a dedicated survey.

Type II-P Supernovae as Standard Candles: The SDSS-II Sample Revisited