Does the author stick to the traditional order of the runes and use only historically attested symbols? (Anyone who insists that a "blank rune" or the "uthark" ordering is valid flunks this test.)
2. Does the author support his opinions with Germanic historical and mythical texts -- not relying on outside traditions or personal revelations too heavily? (People who put runes on Native American medicine wheels or the Qabalistic Tree of Life flunk this test. So does anyone who interprets the runes largely through magical experiments, with no real academic support.)
3. Does the author use the same language for rune names throughout the book? (Calling one rune by its Norse name and the next by its Anglo-Saxon name is bad linguistics, and probably means that the other facts are just as poorly researched.)
4. Does the author distort the meanings of the runes to fit a personal agenda? (An ultra-feminist author trying to eliminate all male references from the runes would flunk this test.)