I don't follow what you're saying.

If you're assuming that the price is ultimately a pretty fair representation of value, the message from price in the last 25 years is that the fair book value per share has been falling, not rising, right?

For whatever it's worth, each quarter I look at book value, and also calculate intrinsic value using a fairly time consuming more sophisticated model. Over time one might reasonably expect some drift between the two, but I haven't seen any yet. If anything there is a very slight decrease in the implied fair P/B in the last decade, though I think that's mostly statistical noise - well within the error bars of both methods. There is no theoretically sound reason to expect P/B to remain a good yardstick of value, but to the best of my ability to determine, so far it's coincidentally as good as it always was and any given P/B number has about the same meaning as it has for a very long time. Emphasis on "so far".

Jim