Really turning on the metaphorical sixpence


Some copy recently submitted to the subs' desk contained a sentence that has been messing with my head:

You really can turn this vehicle on the metaphorical sixpence

As opposed to what, being able to metaphorically turn it on the metaphorical sixpence? But isn't that what the writer actually means? After all, you can't literally turn the vehicle on either a literal or a metaphorical sixpence. Surely?

I think I have been subbing too hard today.