"The issue of reversibility in hydromechanical sprinklers that auto-rotate while ejecting fluid from S-shaped tubes raises fundamental questions that remain unr

"The issue of reversibility in hydromechanical sprinklers that auto-rotate while ejecting fluid from S-shaped tubes raises fundamental questions that remain unresolved" - I thought that was resolved already, by the fact in one case the fluid is expelled outside of the sprinkler and doesn't interact with it, whereas in suction the fluid "bumps" into to curve of the sprinkler and cancels most of the pull of the suction.