Silversage
Head Chef
The way they describe the preservation, you still will not be able to use the rind. I've done it in a very similar way many times and rind is not usable. You do collect a lot of juice though. In my case preservation was not a goal, but a necessity.
The rind and pith are usually the only part that is useful. The pulp is pretty lacking by the time it's preserved, kind of like the mirepoix after making stock. You can use it if you want, but it doesn't add much. The juice is mostly just salt, and unusable.
I always have a jar in my fridge. It's a common ingredient in Mediterranean and North African food.