recently there are a lot of price feeding relevant discussion on Chinese community and wechat groups
https://bitsharestalk.org/index.php?topic=26909.0summarizing the discussion and reviewing what happened in the market these 2 days, I suggest witnesses to adopt a new model for CNY price feeding:
suppose A = BTS price in bitCNY at DEX + bitCNY deposit fee, Bi = BTS price in CNY got from one big external exchanges.
feed max(A,B1,B2...) as the BTS price in CNY.
let me explain why suggest to do so:
there are always shorters who watch the whole market, the dept positions in DEX everyday, and they are clear about the margin called rules in DEX, so when bear comes, they begin their work: sell BTS in big quantity in centralized exchange and lower the fee price and make the big debt position margin called, and they buy the margin called orders to make profits.
surely there should be shorters exist in a healthy market, but it's not good to always encourage shorting and speed up the falling of BTS price in bear market. to cultivate the smartcoin ecosystem, it's necessary to continually optimize the rules to encourage longers and discourage shorters.
the target CR is a very good new feature to do so, but we still need more optimization.
external centralized exchange are not transparent enough, in some market like zb.com, user can borrow BTS and short, and price come from these exchanges are mostly coverted from in BTC to USDT and then CNY, the too long conversion chain involve many uncertain factors.
BTS/bitCNY pair in DEX is the BTS trading pair with highest volume on the earth, and bitCNY has a convenient channel to fiat CNY, so this price can answer exactly in what a price people can buy/sell BTS in fiat CNY.
sometimes the price in one market can be temporarily lower or higher then other markets, if the finally adopted price temporarily higher than the actual price, it lead to little problem, but if the finally adopted price is temporarily lower than actual price, it may lead to margin call which should not happen, this is why I suggest to feed max(A, B)
currently the fed price to DEX comes from centralized exchange, it is like the neck of DEX are grabbed by exchanges outside DEX, we should let DEX itself play more important role in price finalizing, let the longers and shorters fight in DEX, not other exchanges.
to be careful, I suggest only try this model in CNY price feeding at first.