Three tests in three weeks is a tough schedule in anybody's languages but when you're up against the All Blacks and Australia on the other side of the globe, it takes on a different meaning entirely.

Despite three defeats on the trot, and a season that's finished with a 45 per cent win-loss ration, there are some things to be happy about, most notably the side's new found penchant for keeping the ball in hand, and the new found ambition they have for taking risks on the front foot. But they'd be winning games easily if everything was perfect and there are a number of issues that need to be addressed.

Arguably the foremost amongst them is the substitution question. Yesterday, all seven got on the field at some point in the game . . . for the first time on tour . . . but only Bryan Young and Mick O'Driscoll came into the game when it was even close to being in the balance. It was a similar story in the two tests against the All Blacks.

In that first game in Hamilton, it was clear to see that Ireland were punch drunk with 20 minutes to go, purely because of the fact they were being forced to make so many tackles. It was a similar story in the second test, as the All Blacks turned the screw in the final quarter.

But in both games, there was only one substitution made while the game was still in the balance, with Girvan Dempsey coming on for Andrew Trimble in the 66th minute of the game at Eden Park. That's three substitutions in total in three final quarters where Ireland have conceded a total of 37 points.

This policy of not tinkering with those on the pitch just doesn't add up.

Allow us to take a trip back in time, two and a half years back, or just under. Ireland had been knocked out of the World Cup by France at Melbourne's Telstra Dome the previous evening and Eddie O'Sullivan was holding a morning-after-the-nightbefore press conference at the Holiday Inn. Explaining away the defeat, predicting how France would win the World Cup, that kind of thing.

As things were winding up, the Irish coach steered the conversation towards the physicality of the French side his team had been brushed aside by and the problems little old Ireland faced in keeping up with the brutes being produced by England, Australia, New Zealand and others.

"It's getting harder and harder for skill to overcome strength in this game, " said O'Sullivan that sunny morning. "It's a power sport and it's supposed to be a power sport, and might is right in that sense because it gets results.

For Ireland, with the player base we have, that's a certain worry for us about how far up the food chain we can work ourselves. How we get round that is our problem to solve and we need to be even more aware of how we use our resources and recruit resources."

Now skip forward to last Tuesday at the Intercontinental Hotel in Perth's Burswood Casino Complex.

O'Sullivan was in fine form, perhaps because his side had pushed the All Blacks close on consecutive weekends, or maybe simply because with the season almost at an end, he could see the wood from the trees once more. Whatever the reason, his dapper form saw him enter into a longwinded answer about impact replacements which revealed volumes about his personal views on the subject.

O'Sullivan, as you may have gathered from watching Ireland play over the past couple of years, doesn't believe in making use of his replacements bench. In the world of useless, he sees them as being up there with the ashtray on a motorbike variety. You get the feeling if he could travel back to 1996 and brainwash those IRB men who initiated the change in the old substitution law, he'd be riding shotgun with a certain Michael J Fox in the time it takes, well, to actually make a substitute on the rugby pitch.

But here's the thing. If you link O'Sullivan's two press conferences together, he could solve the final question he posed in 2003 by changing his substitution policy, or more accurately, philosophy, it's almost become. How can Ireland hope to keep up and cope with physically bigger teams over the course of a bruising 80 or, as it has become recently, 90 minutes of intense rugby? By using 22 players instead of 15.

Take the Scottish example. They played the Springboks in two tests over the past couple of weeks and although they lost both (36-16 and 29-15), it was hardly the embarrassing sort of stuff they've had to put up with in the recent past. They've undoubtedly progressed as a team under Frank Hadden's control, but one of the reasons is that the coach has decided upon a policy of playing 22 players in every game, not just 15. In both games, Hadden used all seven substitutes over the course of the game but more importantly most of them were given some decent game time on the park. Time to actually make a difference. This example can be extended to most international teams that have been tossing the ball around this summer.

Although heavily understrength, both England and Wales used their bench extensively against Australia and Argentina respectively, while Australia, New Zealand and South Africa, the big winners this summer, all used their benches while in front and you'd imagine they'd be more inclined to do so had they been behind.

The odd one out in all of this is Ireland and it just doesn't make sense. Even more so when you consider at what stage this particular team find themselves. They've taken reasonable strides in a number of key areas since the debacle of November and are now only a couple of tweakings away from developing into a side capable of beating the world's superpowers on a semi-regular basis. They're searching for a few extra per cent here and there to make up the difference and to find that next level, surely they need to try things they haven't done before?

O'Sullivan's stubborn stance unearths three important points. Firstly, does the coach trust his own judgment in the final quarter of games?

Does he feel capable of making the right call, with the right player at the right time?

Does he trust his own reading of games? If the answer to any of those questions is no, it's worrying.

Secondly, if everyone on the pitch at the start of the game feels that the coach is unlikely to haul them off, complacency must become an issue. From a psychological point of view it has to make a difference if, for example, Peter Stringer feels his coach is thinking about introducing Isaac Boss to proceedings at any given moment.

The final point centres on what state of mind Ireland's replacements must be in.

While talking around the issue last week, O'Sullivan gave the strong hint that he doesn't feel his bench is of sufficient quality to use enmasse during games. What kind of an impression does that submit to those named outside the starting 15?

If O'Sullivan is sitting at the proverbial drawing board this summer, attempting to narrow the gap between his sides and the top teams, sketching away with balls of crumpled up paper on the floor surrounding him, he'd do well to take a look at his substitute philosophy and consider not being so intractable with it. It could be the difference.