Well, I just bought a 7.5 recently that blows away all but one 8 I could find, and hangs with many of the 9s I saw on VCP and completed eBay sales-- actually besting many of the 9s in the centering and color department. I chose it over a few 8s that were available to me, as to me it was the better card. I'd also say that I have seen MANY half grade cards sell for much closer to the upper grade than the lower-- all depends on the card. If one buys a high end half grade, likely it will sell closer to the upper grade, I believe.
I'd offer that cards are each unique, discrete pieces, and need to be evaluated as such. Even with the TPGs efforts to herd cards into neat boxes, all cards in the same grade are simply not the same card, and some will not behave according to the VCP pricing grid. I couldn't generalize against an entire specific grade, and it seems whoever landed the Mays 7.5, along with the lucky new eventual owner of that nice Banks 7.5 RC, feels likewise
