Alessandro Padovani pointed out that Blender already has a tool which does this. It is called Bake Action and is found in the Object > Animation > Bake Action menu. Therefore, the new Unwind Action tool has been removed again. The motivation for using it remains the same.
Morphs in DAZ Studio correspond to either shapekeys or driven poses in Blender, or possible to a combination of both. The preferred way to animate morphs is to animate the corresponding rig properties, which is simple enough as long as you stay within Blender. However, driven poses are highly non-portable and not supported by standard export formats such as FBX or Collada. This means that morph animations cannot be readily exported to other applications, e.g. to game engines such as Unity or Unreal.
One way to get around this problem is to convert driven poses to shapekeys, using the Convert Standard Morphs To Shapekeys and Convert Custom Morphs To Shapekeys buttons in the Advanced Setup > Morphs section. This works for most facial morphs, because the face bones are translated and not rotated. However, converting a driven pose to shapekeys has two drawbacks:
1. It is wasteful, because shapekeys take up much more space than poses. The movement of each vertex is stored instead of just the movement of bones.
2. It only works if the bones are translated but not rotated. At intermediate values, a vertex moves along straight lines with shapekeys, but along arcs with bone rotation.
To illustrate the latter point, consider the standard body morph lHandFist.
To address this problem and make it possible to export morphs to other applications I introduced a new tool called Unwind Action, which converts an action with driven poses into an action with pure bone transforms and no drivers.
Since the unwinded action only involves bone rotations and no drivers, it should work if it is exported to other applications.
This is the first version of this tool. There are at least two improvements that immediately come to mind:
1. Some adjustments are necessary if the driven bones have been made posable with the Make All Bones Posable tool.
2. The same rig property can drive both bone rotations and shapekeys, and that case should be handled too.
In the near future these issue will be addressed.