On the other hand, but for international demands, the Addicks might have been turning out at Bramall Lane today as First Division leaders instead of being stuck in the chasing pack five points behind Ipswich.
Because of call-ups, admittedly not just of their captain, Kinsella, Charlton have already played two or three games fewer than their rivals and on 9 October it will be one more. While Charlton are twiddling their thumbs, their First Division home game against rivals Blackburn postponed, Kinsella will be standing on the threshold of a famous victory. Should the Republic beat Macedonia in Skopje the next day, Mick McCarthy's side could find themselves following a trail first blazed by Jack Charlton's Jolly Green Giants 11 years ago, by qualifying for the finals of the European Championship.
The last time Kinsella came that close to fame was when the groundsman at Colchester spread a rumour that the young Dubliner was on his way to Barcelona. That took some believing, not least because while Kinsella may have been their best player, they had only just returned to the League from the Vauxhall Conference. No one can say that the 26-year-old's journey to the top of his profession has been easy. It may explain why even if his appearances for the Republic have left Charlton playing catch-up, Curbishley does not begrudge him his success.
"He appreciates fully everything that is done for him," said Curbishley, who made the job of tying Kinsella to a five-year contract one of his main priorities following last season's relegation from the Premiership. "His success has been well deserved. We're off to Sheffield now and if, when we arrive there, we find a mistake has been made over the accommodation and it's the worst hotel in Sheffield, he would never say anything. He'll just get on with it, because he appreciates how lucky he is to be a footballer. He never misses a day's training and has hardly missed a game since he's been with us."
His international manager is equally full of praise for a player who has filled the huge void left by the international retirements of Andy Townsend and Ray Houghton. He seemed to come of age when winning his 10th cap against Yugoslavia this month with a performance that drew rave notices from Big Jack himself. But McCarthy's enthusiasm was not always as boundless, according to Curbishley.
"Mick lives in Bromley and was getting badgered by all the Charlton fans for not selecting Mark," said Curbishley. "I remember in the year we went up after one particular game in which Mark was outstanding I was quoted in the papers as saying Mick should take a look at him. On the Monday morning Mick rang and accused me of trying to pick his team. He said: `I get enough of your fans driving me mad anyway when I take my kid to school. He's got to do a bit more.' Well he's done a bit more and now he's a regular in his team."
For a player who was told when he was at Colchester that he could not defend, Kinsella has made some progress in that direction, thanks to Keith Peacock and his fellow coaches, who in three years have turned a pounds 150,000 player into one worth more like pounds 1.5m. Kinsella reckons the improvement is about 100 per cent. So much so that he now "sits" for Charlton in midfield. In the Republic side he is given the licence to attack, despite Keane's insistence that "Mark's easily as good as me at sitting". He is, however, still waiting for his first international goal.
"For the amount of forward runs he makes - he's that willing to work - he should score more goals," McCarthy said. "He regularly runs beyond the strikers and ends up running past them on the way back. He's a typical box-to-box modern midfielder. He's got a great engine and he punches more than his weight. He's a Premier League player playing in the First Division."
Not that Jack Charlton will have known, but Kinsella was a member of his Under-21 side five or six years ago, when the senior side were socking it to the likes of Italy. "I just watched and enjoyed it like everyone else," Kinsella said. "I would have loved to sample that and now maybe I will."
Who knows, there could even be "international" recognition of a different kind for Kinsella after Charlton announced a partnership with Internazionale that should involve loaning each other players. Would Curbishley loan them Kinsella? "Only if they gave me Ronaldo," he said.