@matthijs – Vitaly Petrov had the same problem. He was the tallest driver on the grid, so even at the peak of his physical fitness, there was still, quite literally, more of him compared to the other drivers simply because he had longer bones. It was a real challenge for Renault to design the R31, mostly because Nick Heidfeld was the shortest driver on the grid at the time.
Anyway, thus story about Hulkenberg being too heavy smells funny. It reads like something a fan club might come up with: they see a vacancy at McLaren, and they see Hulkenberg without a contract for next year. To their minds, it’s a perfect fit, but when it doesn’t happen, they’re left trying to explain why in such a way that McLaren passing on Hulkenberg sounds as ridiculous to us as it does to them. It’s the kind of thing Petter Solberg’s fan club in the WRC used to do.