Exporters Benefit From Falling Dollar

I found this article pretty interesting. However, I don't see how China can continue to intervene in the currency markets and keep it's Yuan perpetually valued lower than our dollar. That doesn't exactly seem like free trade or fair trade.

http://money.cnn.com/2007/11/06/smbusiness/falling_dollar.fsb/index.htm?cnn=yes

The problem is the dollar isn't just falling relative to other currencies. It's falling relative to actual stuff, i.e. commodities (oil, gold, raw materials, etc.)

This means that the old assumption that a weaker dollar makes cheaper exports doesn't hold for very long, because the prices of most exports are simply going to inflate to compensate for the higher cost of production in devalued dollars. Which ultimately nulls out much of the competitive advantage of the currency drop.