My boss just attended a trade show last week, and he came back really excited about a new product that claims to reduce CYA in swimming pools. I did a little searching, and I was able to find an MSDS and some marketing information. It sounds like the product introduces biological agents to the pool that in turn break down the CYA. I haven't been able to find any information on the recommended use, or the conditions under which it will work. It will be interesting to see how it works.
The product is called Bio-Active.
The first link will take you to their homepage. The second takes you to a PDF of their fact sheet. The third is their MSDS.