(Still can't auto-quote the OP in a thread? /sigh )

@willdial

Yes, this has been known for some time, though it's still worth bringing up since hybrid items can provide a great deal of flexibility and good-quality effects.

One thing to note is that not all clothing items have good geometry at the group boundaries to set up a realistic soft-conform zone. But, for most dresses and skirts that use ghost-bones and handles instead of thigh bones for their deformations, they are usually set up with a nicely defined waist/skirt region that can easily be converted. (I tend to combine both regular rigging and ghost-bones for fine-tuning skirts and similar items that can move independently of the figure's limbs.)

There are a number of products and freebies that are intentionally set up like this. These "hybrid" or "combo" items can be pretty neat, though one often has to hunt for them, specifically.

It's worth noting that buttons, separate trims, decorations and accessories that are supposed to appear "attached" can all be set up to be soft-conforming. Varying the settings for those particular groups can help retain their shape and/or help them follow the underlying geometry a bit better.

Lastly - If one wishes, for ease of use, editing the object file in a product that can edit the UV/Group/Material zones is often the most pain-free way to create a good boundary area. All that is needed is to set up a new material zone and then pointing to that in the Cloth Room. (Select by Material Zone) UVMapper Lite (Free) is probably most people's go-to mapper. Roadkill is another and has a 3D interface to make face-selection easier. Though, saving the resulting object with a new name and then making a copy of the CR2 and editing it to point to the new object is the way to go. Editing an existing object without at least creating a backup is "A Bad Idea." :)