Complex sentence: Skilling joined Enron on the condition that they begin using mark-to-market accounting, which allowed the company to book potential profits on certain projects immediately after the deals were signed, whether or not those projects turned out to be successful.
Split into simpler sentences: Skilling joined Enron on the condition that they begin using mark-to-market accounting. This allowed Enron to book potential profits on certain projects immediately after the deals were signed, whether or not those projects turned out to be successful.