kbrockman
but I seem to remember that the X35 also had similar issues, most notably on one of its final proving flights
I was unaware of that. Having talked to the pilots of both I feel that the event you describe happened with the X32 not the X35.
As to your concerns about about the conservation of energy the ability to hover some 25% more weight using the same basic engine results from a difference in propulsive efficiency between propellers and jets at low speeds.