You can do this today with Multi Sig signature. 3 way keys. They fixed this problem.
I think you are missing my point. I am not slamming Bitcoin for the sake of Ripple. Bitcoin is great.
I am heavily invested in Bitcoin.
I am highlighting the actions of TradeFortress, a former pseudo-anonymous bad actor in the BTC community.
A major problem is centralization around the endpoints of the Bitcoin network (where money comes in and out), as well as
unsolved mining centralization patterns. Exchanges and payments providers generally operate off-chain, defeating the beauty of Bitcoin's decentralized nature. TradeFortress and the like operate in that space.
I hope to see Bitcoin extended over time to support its own on-network decentralized exchange, and absorb other next gen features from the alt community. I expect the BTC community itself will solve for the centralization tendency of mining over time.