"These cases include allegations that 401(k) plan fiduciary committees and their members breached their responsibilities by: [1] Constructing a custom target date strategy that included hedge funds that suffered significant losses; [2] Not using the least expensive mutual fund share classes available to the plan -- or using mutual funds when less expensive commingled trusts or separate accounts of essentially the same investment strategies were available; [3] Allowing the plan to pay excessive recordkeeping and administrative fees in a multiple employer plan arrangement; [4] Using a money market fund rather than a stable value fund as the plan's cash-equivalent alternative."