What difference would a Tegetthoff-class squadron make at Jutland as a German ally?
Short answerIt would strengthen the line and outperform some early German dreadnoughts, but probably would not change the result.
NotesThe Tegetthoffs would be useful without proving decisive in this counterfactual. Their 12-inch guns and overall quality would make them more valuable than some early German dreadnoughts already present. They could contribute effectively against the older ships in the Grand Fleet's line. The extra squadron would strengthen the High Seas Fleet without overcoming the larger factors that determined Jutland's outcome.