What does the Miragedrive idler do?

I was recently sailing and due to a running repair the idler was disconnected. This didn't impact on the drive at all so I'm wondering what it's function is aside from looking good

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Cheers

Jeff
AI (2016)

Great question. When you push on one pedal, the idler transfers some of the force to the other drum, so both drums "pull" the fins. This makes the action smoother and reduces peak stresses on the individual components. It works without the idler, but your cable/chains and other parts will fail faster.

Thanks Roadrunner for your comprehensive answer. There were all sorts of theories when we discussed this; a money spinner, a hypnotizer or fascinator, a safety feature as an attention grabber to keep you looking forward

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Cheers

Jeff
AI (2016)

I know this is an old thread, and I know that Roadrunner knows his stuff. However, I'm not convinced that the idler cable does anything useful.

I'd estimate that I put nearly 1k miles on my GT drive over the course of a fishing season. I got tired of paying for idler cables, so for the past few years, I've replaced the idler cable with a bungee cord. It has just enough tension to move the idler pulley, but I don't think it does much of anything--certainly it is doing a lot less "work" than an actual cable would be doing. Using this bungee cord trick, I've not noticed any difference in the wear of the chain/cables or any other components.

I think I'm going to completely remove the bungee cord/idler and see if I notice any difference...