I do the slowing down hand signal too (like signalling, but waving arm up and down a bit) - either they realise you're slowing and give you more room, or get confused by the unknown signal, and give you more room.
If I'm being tail-gated, I show them my palm, with my fingers pointing downwards, and do a sort of 'back off, please thank you very much' gesture.
They won't work if the driver's psychotic/daydreaming/otherwise distracted, but what can you do...
I do the slowing down hand signal too (like signalling, but waving arm up and down a bit) - either they realise you're slowing and give you more room, or get confused by the unknown signal, and give you more room.
If I'm being tail-gated, I show them my palm, with my fingers pointing downwards, and do a sort of 'back off, please thank you very much' gesture.
They won't work if the driver's psychotic/daydreaming/otherwise distracted, but what can you do...