In their recent paper, Orrisetal. (OMK) [J. Acoust. Soc. Am.96, 3499–3503 (1995)] present the ‘‘matched‐phase noise reduction’’ technique, which they characterize as a ‘‘method for improving signal‐to‐noise ratios in noise dominated data, given the shape of the noise spectrum.’’ They derive an optimum ‘‘filter,’’ analyze its properties, provide ‘‘an example in which a signal can be retrieved from noise at a level more than 100 dB higher than the signal,’’ and suggest practical applications for the method in underwater acoustics scenarios ‘‘where the frequency spectrum is known approximately.’’ The present paper analyzes the OMK technique in terms of estimators that best approximate the unknown signal and noise and arrives at conclusions which differ from those of OMK. The demonstration of signal recovery reported by OMK is shown to result from their synthesis of an atypical noise realization. Limitations of their technique under more typical conditions are derived.