So I thought this was very interesting and relevant. It relates to the class example we did with Rob Baker.
Many funds have upper limits on the proportion of the fund that can be invested in one asset class. Proportions are determined by comparing the value of the assets within each class to the total value of the portfolio. If you think about it, by using a more conservative valuation method for equities (e.g. book value in most cases), fund managers can get away with holding a greater proportion of their portfolio in equities than if they had used market values.
Now I imagine there is some kind of regulation prescribing the methods that fund managers must use to value their assets. The point remains: valuation methods do not only affect buy/hold/sell decisions for individual assets, but they also affect the make up of the portfolio by asset class.