The paper mentions mixing services but suggests that they are unsuitable for large-scale laundering due to their relatively low volume. That is, if someone want

The paper mentions mixing services but suggests that they are unsuitable for large-scale laundering due to their relatively low volume. That is, if someone wanted to cash out thousands of bitcoins, it would not be possible to disconnect the block chain trail as the value of bitcoins being transferred would dwarf the rest of the transactions being mixing in.