As now, if I attempt to convert bitCNY into bitUSD, I have to go through bitCNY:BTS and bitUSD:BTS market since bitCNY:bitUSD market is not that active. Plus, when I go bitCNY:bitUSD market, the wallet says "insufficient feeds" although there're already enough feeds for USD and CNY. We can easily create the bitCNY:bitUSD feed with medians of USD and CNY and this can be applied to relative order function in this pair.
With relative order in a pair of BitAssets, people won't be bothered by spread of both CNY:BTS and USD:BTS market. Once market makers come to bitCNY:bitUSD market and with some spread (I guess 1% or less), people are able to convert their local currency into foreign ones.