Replication is a key principle in tree-ring research. Dendrochronologists strive to maximise sample size to enhance the "signal" in tree-ring chronologies, often relying on crossdating to provide an effective quality control filter. However, is crossdating alone a sufficient quality test for incorporating a series into a site chronology? We address this question using an objective and automated "chronology stripping" method designed to maximise the chronology's "Expressed Population Signal" (EPS), by iteratively removing series which lower chronology EPS. A 15-site data set of Agathis australis (D. Don) Lindley is used to demonstrate the method. Results suggest that modest benefits may be gained by chronology stripping, but the quality control implicit in crossdating is indeed effective, at least for Agathis australis.