blargh
Member
- Location
- Redwood City, CA
- Occupation
- Design Engineer
My best guess is that the single required 20' piece of rebar embedded in the slab provides a "good enough" electrical connection to the larger conductive grounding mass of the concrete slab, and any electrical connection (via tie wire or otherwise) to the rest of the rebar system is a "bonus" but unnecessary to achieve the design goals.