Instant death is a misnomer. There's no such thing as "instant death". It's a relative term. What is an "instant"? A second? Two seconds? Ten seconds? If you jump from 267 feet and land on your legs, your legs are going to absorb the force before they can no longer absorb the force, and only then will bones begin to shatter. The force continues up through your hips and into your spine. There is going to be some discomfort, to say the least, and I think it will be felt. For how long, I don't know. Even if your spine severs, the heart will still continue to pump for some period (short) amount of time. There will still be blood in your brain. Necrosis does not start instantaneously. LE, doctors, etc like to use the term "instant death" in order to comfort the grieving in believing that their loved ones did not suffer.