Pulling off a compelling change of persona is an undertaking seldom pulled off instantaneously, more often requiring a significant period of adaptation.
For every Bobby Boucher in the Waterboy, there are a thousand nascent shopping mall goths, self-consciously shuffling around in Peter Storm anoraks for month-upon-agonising month while they save up the cash for their maiden leather trenchcoat.
The summer holidays are not always of sufficient length to affect such a change of tack convincingly.
So it has proved for Liverpool and West Ham, who can sympathise with budding children of darkness as they gear up to face each other for their teatime tussle at the Boleyn Ground.
The Reds are 17/20 favourites for victory, with the Irons 13/4 outsiders and the draw a 14/5 wager.
However, with Brendan Rodgers’ men yet to prove their ability to mix it on a post Champions League awayday, the 7/4 about over 3.5 goals in the fixture is more tempting than any of the match-betting morsels.
Why? Let’s extend the metaphor.
Last year the Merseysiders were going out with the most prolific striker in school, their classmates jealously telling tales about how easy they were to score with behind their backs all the while.
They’ve returned for the new season without the allegiances of dreamy badboy Luis Suarez, intent on harbouring a reputation for parsimony.
However, attempts to play in a less defensively-suspect manner have so far succeed only in disrupting the understandings that made them so irresistible in the first place, making them a beatable proposition for the likes of Aston Villa.
West Ham, on the other hand, have been compelled to cast off their commitment to playing it safe if their work is ever to appeal to the top end of the mark-scheme.
However, the effect of shedding their long-held inhibitions is so far a dubious one, with five goals shipped inside their last two outings.
With the joins still visible in both sides new personae, savvy punters are advised to cash in on their lack of cohesion by backing over 3.5 goals in a fixture that has seen the bet cop in two of its last four renewals.