Plug-in gives Layers to LR and Aperture

I am not a PS user, but I do use LR. What would a simplified (because that's what it looks like) Layers program give you that LR can't do with it's localized brush? Sharpening, exposure, contrast, etc. -- all localized -- can be done with the brush, including with an auto-mask. What would this layers program add?
 
Historically, I didn't use layers much as my equipment (computing power or lens quality) always seemed lacking ... that's right, it's the equipment's fault not mine :)

But I no longer have that excuse, so I hope to be pleasantly surprised like I was with LR3 and will give the demo a try.
 
Back
Top