Why a 14-inch Scharnhorst is not a simple option

What about a Scharnhorst with nine 14-inch guns?

Germany lacked a 14-inch gun programme, so the apparently neat compromise would add a major new development burden.

The proposed battery is attractive on paper, but warship design must start from machinery and weapons that an industrial system can actually produce. Germany possessed an 11-inch programme and was developing 15-inch weapons, not a mature 14-inch line. Creating a new caliber would add design, testing, ammunition, and production burdens to an already constrained programme. A plausible counterfactual design must respect national supply chains rather than mix ideal components freely.