Certainly for club-running, Liz and I go like stink onna tandem. We're definitely better together than when we're on solos. When we're blatting along at 38kph on the front of the pack, we've still got breath left to sing rude songs, whilst the people behind struggle to keep on. Mind you; although we did a few shorter audaxes on Margaret Hilda - we've yet to take Josephine on a proper Audax.
Interestingly, I rode Josephine solo on Wednesday night and although it's harder work than riding a solo, I can keep a respectable 28kph on her on the flat. Kind of like riding a hefty touring bike, really. But as soon as I collected Liz from the station, it was like, "whoa, baby!" A different league.
So yeah - I think tandems are cheating. And I'm all for them