All animatable properties let you reference several controller-related sub-properties. These are:
.controller -- the property's controller
.track -- ditto
.isAnimated -- a boolean indicating whether property is animated
.keys -- readonly, gets the controller's key array
.value -- get or set the current controller value
The .key and .value properties give you access to the value and keys in a free-standing controller, which is useful when working with the global tracks controllers that are accessible in MAXScript.
The .value property is sensitive to the current time and animate contexts, so you can use it to evaluate a controller at various times or to plant keyframes in those controllers that support keys.
$foo.pos.controller
bend_mod1.angle.isAnimated
$bar.taper.gizmo.scale.keys[2]
The .track property is a simple synonym for .controller. If an animatable property does not yet have a controller assigned, the .isAnimated property returns false and the .controller/.track/.keys properties return undefined.