Some 17 months after first emerging as an activist investor in Navios Maritime Partners, “disgruntled” Ned Sherwood is back and seemingly searching for new adjectives to express his frustration with leader Angeliki Frangou.

The veteran US-based finance man is out with a new open letter to Frangou and the Navios board, in which he repeatedly mocks the chief executive’s oft-stated expression that she is “pleased” with the company’s performance.