The foundation of Tango is the walk, and the foundation of that walk is the weight change. However, the foundation of the turn in Argentine Tango is in fact Disassociation. Any turn that has any level of ‘circularness’ to it, contains a level of disassociation at its core.
To be clear, disassociation is not a Pivot. They’re not the same things (look here). It’s important that we make the distinction between what it is and what it is not. Put simply Disassociation is split level rotation around the spinal column. Whereas a ‘pivot’ is the rotation of an entire object over a singular point (see the link)!
Every Ocho, Sacada, Molinete, Gancho, Circular Boleo, and Wrap has an element of Disassociation built into it that we want to use, and then exploit to our greater visual coolness!
The reason we want to use Disassociation over a Pivot are wide and varied but the simplest reason, aside from its coolness factor, is that it gives us a greater range and degree of control and precision in nearly everything we do and that we want to do. Put simply, it’s the game changer. A Pivot is nice if you want to move like a block of wood. Disassociation on the other hand is like a whirling dervish on steroids! But the real toy, the real amazing toy is Applied Disassociation! That is really the Holy Grail.