Only if the change is localized to specific blocks.

Besides, block-level dedup is expensive to maintain. Unless you're expecting to find a lot of duplicates -- which probably isn't the case on most end-user devices -- it's a net loss.

Expect about 30%, most of it in smaller system files and libraries. Block-level dedup is great for pretty much anything where you have a consistent workflow.

A consistent workflow sounds like something you’re going to find more regularly on a server than a mobile device or home computer.