I agree about the feet tapping at two or even three different speeds - just try leading a session in a long narrow room where neither end can see or hear the leader in the middle - bit like a 'sturmey archer' session! i.e. 3 speed. just to give things a furthur stir - many classically trained persons have great difficulty keeping good time without a conductor whereeas foot tappers can at least keep an eye on everybody elses feet & hopefully keep some sort of synchronisation that way - your turn Robin.
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