Much of this is down to the complexity of valuing a firm's assets in the digital age. But the result is that price-to-book is a bad guide to a stock's true value.
New CEO announcements have moved stock values up or down by double digits so investors and the boards that represent them sometimes pick the safest option over the best option.
Par value, in finance and accounting, means stated value or face value. From this come the expressions at par (at the par value), over par (over par value) and under par (under par value).