Amazon, Berkshire Hathaway and J.P. Morgan have announced a nonprofit initiative to address excessive spending on health care, starting with their own million or so employees. They can expect many suggestions. Here’s one: The three CEOs— Jeff Bezos, Warren Buffett and Jamie Dimon, whom I’ll call “BB&D”—could do a huge service by describing the depth and nature of the cost problem, something politicians have long failed to do.