Stewart Fisher: Would you want your child to sign for the other half of the Old Firm?

Okay, I know the equation is imperfect. You might look at the likes of James McCarthy or Craig Sibbald and decide that a provincial club like Hamilton or Falkirk would be a better first step for your precious flesh and blood. You might even look at Andy Murray or Laura Muir and say the best bet for sporting success is to specialise in anything other than football.

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But what if we raised the stakes a little? What if we said you could also make the footballing equivalent of a Faustian pact - and that signing on the dotted line for your dreaded rivals was also a guarantee of lifelong happiness and untold riches for your progeny. A gaze into the future sees them delivering copious amounts of silverware, all of it at your favourite football club's expense.

Would you (a) leave your hang ups at the door and insist that for your child's welfare has to be uppermost? Or (b) tell them to do one and instead hold out for an offer which never comes from the other half of the city?

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Incidentally, while this equation seems to work best for Rangers and Celtic it is by no means mutually exclusive. Try inserting Dundee/Dundee United, Hearts/Hibs, even Morton/St Mirren. Things don't get any easier.

If, when you have had time to think about it, your answer is (a) then that is, of course, the correct answer. And the politically correct one. Football, after all, is a sport first and a business second. What politics and even religion sometimes have got to do with it I am not entirely sure.

While every football club in the land exerts a sense of community and belonging - and usually picks at least one nearby club as its 'other' - the received wisdom is that football is a short, brutish career where the only true loyalty a football player has is to maximise what you make out of it.

Football is littered with players who grew up appreciating one side of the divide only to star on the other. Kenny Dalglish, Maurice Johnston and Scott Brown were an unlikely trio who crossed that particular Rubicon way before Joey Barton came into view.

Players shouldn't feel bad about this. So, mainly, they don't. Because usually they are the ones on the receiving end. Loyalty is all well and good, but being born in the shadow of the stadium is no guarantee of a first team place if a player, be he from South Korea or Nigeria, becomes available who could upgrade that position. In fact, allegiance to one particular club is often only an invitation for that club to drive a harder bargain.

Even at youth level, Rangers and Celtic eye each other's talents jealously, keen both to poach the best players and deprive their main rivals and individual loyalties are all part of this matrix. One promising young player, from a Rangers supporting family, was training with both Rangers and Celtic as a teenager, only to be let go by the Ibrox side - days after the Parkhead side had filled their squad. He ended up elsewhere altogether and thankfully doesn't seem any the worse for the experience.

Then there is the strange case of Dylan McGeouch, the classic tale of a boyhood Celtic fan who signed with his heroes, only to be stolen across town to Rangers as a 15-year-old, partly because of some ill feeling caused by the release of his brother Darren, also a boyhood Celtic fan, from the same Parkhead youth ranks. A personal visit from Neil Lennon say Dylan move back to Celtic again - all before the age of 18 - and now the two men are together at Hibs. Liam Burt, currently on the fringes of things at Rangers after an upbringing at Celtic, was another young man briefly linked with making the return journey.

But if your answer is (b), what does that make you then? A 'fundamentalist', as one radio pundit would say? Part of the problem, rather than part of the solution? Or merely someone whose principles - however counter productive - are not up for the highest bidder?

Fans love nothing more than signing 'one of their own'. Spurs fans sing that song about Harry Kane, even despite the photos on the internet which show him clad in an Arsenal shirt, with his hair dyed red in homage to Freddie Ljungberg. Football once revolved around one-club men, who became heroes of their community. While there are still occasional tugs on the heart strings, like Craig Wighton - from a Dundee-daft family - being persuaded to decline the chance to follow pals Ryan Gauld and John Souttar to Tannadice, loyalties are more malleable now. The real anthem when it comes to relationship between the modern-day footballer and his club belongs to an older vintage. If you can't be with the one you love, then love the one you're with.