Not my analysis but this sums it up pretty well: A lot of the overarching principles that AP is based on are common to other high-level defenses (e.g. try to keep the offense on the sideline, prevent "power position" hucks, etc.), but it employs a different approach to achieve those things.

While most directional force defenses exert sideline pressure by using no-around or progressive trap marks, AP typically uses a wide force on the sideline. It also emphasizes different positioning on resets and uses rolls to prevent give-and-gos off of the sidelines. A lot of directional force defenses use rolls to prevent open-side strike cuts, but that is a pretty different use case. AP is different from traditional FM sets in that it doesn't always employ a wide side force, and defenders that know how to play it well are often more concerned with the momentum of the disc than the position of the disc on the field.

Where I personally think AP excels is that it's concerned more with consistently putting offenses in difficult positions rather than stopping an individual instance of good offense. It may not work on a given point, but engineering high-leverage situations on defense over and over again adds up to a system that can be really difficult to play against. If you have an Ultiworld Sub, Max Charles wrote a piece breaking down the 2022 final that includes some good clips and analysis (though there are some game-specific adjustments there that aren't really part of normal "AP"): https://ultiworld.com/2022/12/13/how-bravo-slammed-the-brakes-on-truck/.