Although today’s term has an official dictionary definition, and approved spelling, the fact that it can been found written as shufty and even shoofti, is a reflection of how it came into being.
Take a shufti began as a bit of verbal business between bantering servicemen in the Middle East. The word shufti derives from Arabic شفتي (šufti, “have you seen?”), which in turn comes from شاف (šaf, “to see”).
As a British term, it first gained popularity among the airmen. There’s some discussion over when this will have been, as it wasn’t written down until the Second World War, but it’s widely reported to have been in use long before then. And to be fair, it has the ring of 1920s toff to it. Presumably some well-to-do pilot, talking to a local guide, will have seized upon the word, after hearing it spoken in combination with a gesture towards some object in the far distance:
Guide: ” شفتي ”
Airman: “Bally fellow wants us to have a ‘shufti’ down there, what on Earth do you suppose he’s pointing at?”
Airman 2: “Dashed if I know old bean. Go on then, I’ll take a ‘shufti’ if you will… (conspiratorial laugh).”
Before long, everyone was taking a shufti at everything, even the rank and file soldiers in the army. There were even derivative terms, as if there was a need to take this new word out for a spin and see what she was capable of. So an exploratory medical instrument, used to discover if a patient had dysentery or not, was rechristened the shuftiscope. It’s hard to imagine an ickier name, but there we are, extreme circumstances can provoke extremely odd reactions.
After the war, it fell out of use, apart from people mocking that stiff upper lipped RAF pilot mode of speech. The Brigadier in Doctor Who, for example, will have been well aware of it.
And here it is, being used to devastating effect as the punchline to the Peter Cook / Jonathan Miller section of the sketch The Aftermyth of War, from Beyond The Fringe, which was first performed only 15 years after the war ended.
Seriously though, only 15 years! The Spice Girls are longer ago than that.