yeah he notches the shelf around the legs, adds complication for no reason. It lies flat against the wall nice though. I have 4 of the ones you're looking at at work along with a bench that is a full sheet.
edited my post a bit
you remember the not 8' studs?
line up your now decked boxes on the floor the same way, space them evenly, add your legs, flip, add legs. Done. Also moving the legs inboard helps distribute load better, based on the design and the neatness of the workspace he's got to be an engineer, they can over complicate the easiest of things.
the ones at work have a center cross bar and 6 legs, they can support 200 lbs plus per shelf without issue. we have one loaded with paper boxes full of files and I can still climb it like a ladder