Not all markets need to have highly liquid trading outlets in order to be thought of as such. Inefficient markets are where there is an imperfect matching mechanism.

Demand and supply are reflected in the market in the following two prices:

- BTC/USD

- Average transaction fee levels * Average transaction volume rate. In other words, this is the block-by-block, remainder of the block reward after subtracting the subsidy and priced in BTC.

Actually the first one is the only proxy reflecting the current and future promise of Bitcoin, while the second only reflects the present. Miners would be uniquely placed to know how best to vary the block size to maximize their profit resulting from these two prices. The fact that they are unable to is limiting their collective profits, reducing competition between miners and increasing the average tx fee for users.

In that respect a dynamic block size voted on by miners periodically would go some way to rectify this inefficiency. This needn't have to happen on the block chain itself; we could have a continuous prediction market for the block size, and the informed participants (miners) would stand to profit from the uninformed from trading in such a market. How to get the block chain to use the block size thus determined is another technical matter.