A German jump to 14-inch guns

Would German adoption of larger main guns have worsened the naval race with Britain?

Yes; Britain would likely answer with another calibre increase, though an early German 14-inch gun could have made the challenge much more potent.

German adoption of heavier guns would probably prompt Britain to respond with still larger weapons, turning the competition more explicitly into a gun-calibre race. German gun technology was capable. Using the construction delay to jump directly from 12-inch to 14-inch weapons could have produced very potent early dreadnoughts. Procurement constraints mattered, but Kaiser Wilhelm's political influence might have supplied the pressure needed for such a leap.