The E-P system is a simple one. Take what the defense will give you. You can be a power running team one week, a spread out air raid offense the next, a balanced attack that keeps teams guessing the week after that. You can put up points in a hurry, or slow the pace down to a crawl. It doesn’t need specific personnel. Since specific types of players aren’t required, it opens up more possibilities when drafting players or signing free agents. For a team that drafts best player available and not necessarily positional need, like the Ravens, this is a great fit. In fact, in the modern NFL where players are changing teams all the time, and some guys are fits at multiple positions, it’s anyone’s best guess why teams would still chose to run offenses with little wiggle room for personnel changes.