I dont think you should look at the tokens as fractional reserves, the reserve is merely a tool for liquidity and usually when speaking about fractional reserve the reserve is the thing that gives the value to the coin which in this case it isnt. its just the market depth for liquidity in this case or atleast thats how i see it from what i read
Collateralized token is very nice thing which has a number of use cases and reserve can provide some liquidity, which will depend on its size. You can manage liquidity with a smart contract by keeping constant CRR, or you could use this reserve to put buy/sell orders on exchange and manage it with a trading bot, the result would be the same. But saying that 1% of reserve will make a token fully liquid is a complete bullshit. Also, if token B is backed by token A at fractional CRR, it does not make sense to use token B as reserve for token C instead of using token A. This is an infinite money multiplier.