Consider the evidence from St Andrew's, Curbishley's old stamping ground as a player, where Darren Bent's early goal and valiant resistance condemned Birmingham to a third successive home defeat. Apart from the five men on the bench, six potential first-choices sat behind the dug-out, a warning to those on the pitch that their places will be in jeopardy in the event of Charlton's seemingly annual slide down the table.
Curbishley listed those players not involved in his 600th League match as manager. They included the unfit Kiely, Euell and Holland, plus Bothroyd, El Karkouri, Sorondo, Lisbie, Johansson and Ambrose.
"I could easily name another team," he said. "It's a long season, as we've found out on plenty of occasions."
Curbishley admitted he was tempted, after several of his squad played two internationals and made long trips during the week, to sample his new-found depth. "But I'm not that experienced as a manager," he said, self-mockery mixed with sarcasm towards those who vilified him during last season's collapse, "so I left in the ones who've been doing it."
Charlton are unlikely, in the long run, to be among the sides challenging Chelsea at the very summit. But they peaked at seventh last spring before finishing 11th, and there is no reason why they should not emulate Bolton and Everton by planting their flag in Europe.
After they won at Sunderland and Middlesbrough, their slick counter-attacking earned plaudits. Here, in the face of strong second-half pressure, they showed tenacity, resilience and a capacity to maintain the defensive shape.
Their cause was helped by the early departure of Emile Heskey, who might well have profited from one of the many centres swung in by Birmingham and negated by Chris Perry and his colleagues. Yet the best cross was delivered by Jerome Thomas and headed in by Bent for the England squad newcomer's fifth goal since a summer switch from Ipswich. Curbishley, with the Test match on television behind him, likened the trajectory to Matthew Hoggard at his most unplayable.
Birmingham's manager, Steve Bruce, is himself experiencing the reverse swings and arrows of outrageous fortune. Curbishley recalled that Bruce phoned in solidarity after Charlton's 4-0 defeat by Manchester United in May, which prompted him to ponder aloud whether the fans on his back might be right. "Steve told me: 'If you think you're in a mess, where does that leave the rest of us?'
"Then Sam Allardyce called too. People asked me recently whether the next England manager should be foreign. What would they have thought if I'd said yes? I was trying to say that there are a lot of us [English managers] around who have quite a bit of experience.
"Steve is one of them - he hasn't just arrived. He knows the start isn't everything and Birmingham will pull out of it. They won at West Bromwich in the previous game, and if one or two things had gone their way, things could have been different today."
Talking of which, the media told Bruce that TV replays showed Chris Powell had handled a goalbound shot. "Sums up me bastard luck," he grimaced.
Bruce is a victim of his own success in that he has raised expectations, much as Curbishley has in his long tenure at The Valley.
Pressed for the secret of his longevity, the Charlton manager said: "It only comes with getting results; this is a results business. Our average gates and wages are in the bottom five of the Premiership. But if you're a stable club, like ourselves and Birmingham, you can ride any sort of knock."
Goal: Bent (15) 0-1.
Birmingham City (4-4-2): Taylor; Melchiot (Gray, h-t), Cunningham, Upson, Clapham; Pennant, Jarosik (Izzet, 77), Butt, Johnson; Forssell, Heskey (Pandiani, 10). Substitutes not used: Vaesen (gk), Clemence.
Charlton Athletic (4-5-1): Andersen; Young, Perry, Hreidarsson, Powell; Rommedahl (Bartlett, 55), Kishishev, Smertin (Fortune, 90), Murphy, Thomas (Hughes, 67); Bent. Substitutes not used: Myhre (gk), Spector.
Referee: M Halsey (Lancashire).
Booked: Charlton Andersen, Perry.
Man of the match: Perry.
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