Field note · 28 January 2026
When a single lane becomes a policy risk
Boards hear slogans. Plants feel mill calendars. Concentration is a purchase-history problem before it is a speech.
A single lane is not automatically foolish. A specialist mill that has run a tight tolerance for a decade may be the correct commercial choice. It becomes a policy risk when nobody can say what happens in week two of an outage, and when the backup exists only as a logo on a dual-source slide.
In advisory sprints we ask for the last actual shipment from the supposed second house. Silence is an answer. A trial lot from three years ago is a weak answer. A standing purchase order with a small monthly quantity is a stronger one, even if unit cost is slightly worse.
Taiwan exporters sit on a hinge that policy talk loves to simplify. The useful work is still local: which SKU, which mill, which berth, which air exception. The Board Briefing Half-Day exists because directors sometimes need that hinge named in twelve slides, not eighty.
We will not pretend a six-week lab removes policy risk. It produces a brief a plant manager can keep. If the board wants a geopolitical essay, they already have newspapers. If they want a named backup, they can write to the desk.