"Mutual funds that own hard-to-trade debt are gunning for an advantage when it comes to returns, but they can face a big disadvantage when it comes time to sell. They are often the weakest hand in a market of hungry experienced traders simply by virtue of their structure. They must publicly report their holdings, albeit on a delayed basis, and disclose information about investor inflows and outflows. Hedge funds, on the other hand, do not have to disclose nearly as much. That’s like putting a huge "kick me" sign on these mutual funds when investors start asking for their money back."
See:
Bloomberg