"X11, a chained ...." => needs better flow
"creates much slower advancement of mining technology" = a bit vague (?)
"to provide quick responses" => quick response to large mining power fluctuations
"This came at a cost" line, needs rephrasing for better flow.
"This
thas implications"
"In 2014 we realized that we could make a cryptocurrency that used a decentralized version of
CoinJoin as its implementation for anonymizing transactions, we have named this DarkSend. "
=>
"To solve this inherent problem of privacy, we created a new crypto-currency (DarkCoin) that used a decentralized version of CoinJoin in order to anonymize transactions. We gave this implementation the name DarkSend.
Great suggestions, Updated.