Retrieve speed is needed to generate the vortex forces that make these lipless multi-jointed baits swim.
I've no experience using them (they are plastic after all
) but it would not surprise me if the needed retrieve speed in still water offsets some of their appeal. Sweeps and pauses might get around this, I suppose.
I have seen large fish taken on both Sebile's glider and swimmer at outflows, both by night and day.