I'd guess the watt saving being that close to each other is more than 50% for the rear rider. Would love to see some PM figures shared here though.

GCN has two videos racing 1 cyclists, and 2 cyclists drafting with each other vs tandem. The tandem won both efforts.

Pretty sure on a FLAT TT, any typical rider in the rear will only help the front rider. Aero penalty is small for that rear rider, but even if they push only 70 watts, that's a huge assist to the person in front (I'm not sure it's +70 watts advantage, but it's a lot.)

I've been passed by tandem bikes where I know I was significantly stronger than the (old retired) dude in the front and his not-hardcore older wife as the rear passenger. And I was going super hard, like nearly all out, at like 350+watts (it was only a short sprint!) but the tandem still passed me. That old guy alone would have had zero chance against me in that same sprint.

There's a cheerful older couple I often see on my weekend morning runs, tooling around on their tandem.

They must be well into their 70s, so I can assume that they've been married for quite some time. Still they go riding together at least once a week, and maybe more ... and you can't go riding any MORE "together" than on a tandem. I admit, there have been steamy Summer mornings that I've seen them, and the woman has stared me straight in the eye with a "This is bullshit!!!" look on her face, but she's out there with him just the same. She's the stud in my book; anyone can train when they feel like it, champions train when they don't.

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"What's your claim?" - Ben Gravy
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