Starbäck (1828-1885) wrote at length, yes he did. He could write at length about anything, as could Saxo Grammaticus. But about the name change, Starbäck has just one sentence. Starbäck gives no sources, and has no source value except for about history teaching in Swedish schools in the 19th century. His story about Styrbjörn Starke is here - entirely uncritical. /