This is the fourth set of extended comments I have been asked to make on this evolving manuscript, my third effort having been a 27page rejoinder prepared for publication. The original version of the Pierce-Rose piece contained, in addition to several interesting and fresh ideas, a lengthy section impugning my methods, common sense, and good faith in reporting the work I did years ago with what I called the black-and-white model. This polemic rested, as it has turned out, on a labyrinth of factual misconceptions as to what I had actually done or why, underpinned by some embarrassing confusions on the authors' part with respect to elementary distinctions in the philosophy of science, the nature of attitude measurement, types of error structure and the like. The majority of these flaws, including the ad horninew elements and the most egregious factual errors, have been progressively weeded out over three distinct versions of the manuscript. But in each new version new inaccuracies or misleading statements have relentlessly appeared, requiring another round of commentary on my side. As of this writing I have spent well over one hundred hours in these tutorial communications, a matter which may help to explain why my patience has worn thin. A small fraction of this time has, as it seems to me, been well spent. One of the dozen or more issues covered below-that regarding the effect of response set in these estimates-was left unexplained in my original article because of space pressures, and I am pleased to have an opportunity to discuss it here. The other nine-tenths of the time and space has been spent, however, either on direct misreadings of things made clear in my original text that seem to have caused no confusion among astute readers in the profession, or on matters usually sifted clear in elementary statistics courses. I have doubts as to whether any of this has been worth anybody's time, or surely this much space in the Review. However, even in its current version the Pierce-Rose piece seems likely to stir up a maze of unnecessary confusion, and hence requires this fourth rejoinder.