The manuscripts has been provided with 2 good reviews, each positive about the manuscript but one that wants to see more core results to come out of the approaches taken to show what the benefits are more clearly. Neither reviewer had any complaint about the methodologies except for minor points and clarifications. The authors responded well and agreed to improve their analyses of the results. I'm more than happy with these exchanges and look forward to reviewing the changes to the manuscript the authors suggest they will do

The authors have done an excellent job of editing their manuscript and dealing directly with both the core and minor reviewer comments in my view. I appreciate the extra effort with highlighting additional diagnostic benefits of using PCA. I'm very happy with the paper which has always been identified as a good paper by the reviewers. So this can now move to full publication