Let's call the whole thing off

Title of a song from the 1937 musical Shall We Dance, in which Fred Astaire and Ginger Rogers rollerskate around debating the way to pronounce words like "tomato" and "potato". Thus, always gets said by Mark Kermode whenever the pronunciation of a word (usually in a film's title) is in debate, such as "Thermopylae" in 300, the eponymous dahlia of The Black Dahlia, and the erstwhile sponsors of the Sony Awards.