well I think this is complete bo**ocks from my good mate Simon. I would tell him so and send it back. The (my) R500 which must be harder to map than an R300 was horrible when there was something wrong and superb when all was working well. It had several cycles of working well/broken so it was no coincidence.
And yes when it was working badly, foot-bounce made it worse, but it is a symptom not a cause.
I don't think it's the price of razor sharp response and I have no idea why Caterham can't be bothered to get it sorted, but I think it's very, very poor.
Ahh, I feel better now and I don't even have an Rxxx to get up tight about!
Graham