. . . replacing the player's own OBP and SLG in the RC formula with the resulting team OBP and SLG . . .
That's one way to go about it, but my sense of it is that it was devised to get around the problem that most of the sundry formulae then running around were felt to over-estimate power, and that the "nine clones" approach would thus over-state the value of home-run hitters.
The first part was, in general, true" most or all of The Usual Suspects did tend to over-value power; but the defect is easily identified, which is that they did not--few if any do even now--take into account the "compound interest" effect of on-base percentage. By that, I mean that a high OBP certainly increases the probability that a given player will get on base, and thus end up becoming a run scored; but
it also acts to increase the total number of men who will come to the plate in a game, thus also increasing the number of men who have a chance
to get on base and later score. Because The Usual Suspects did not, so far as I ever saw, take that compounding effect into acccount, they did not so much over-estimate power as under-estimate (in a relative sense) OBP.
The formula I have long used, and its efectiveness, can be seen at the here-linked page of The High Boskage Baseball Site
. What pleases me about the graph of predicted vs.
actual is that the most extreme points, high and low, are almost perfectly on, demonstrating that there is no systematic bias toward high- or