It does, of course, have some indirect importance, through secondary media coverage. The following day's newspapers will give acres of space to judgements about the protagonists, which may have some impact. The fact that the debate is happening earlier in the campaign than usual will allow the Sunday papers to have a go, too.

Let's start with a health warning.

Your greatest asset, in your day-today work, is going to be your greatest liability in the debate.

You're steeped in the details, in the statistics, of every policy. So why's that a liability? Because viewers aren't interested in detail, statistics or indeed policies. They're interested in end results. In the difference the policy is going to make. To them personally. Or to individuals they can imagine and identify with.

Bottom line: if you feel the urge to talk GDP, don't. GDP is one of the deadly turnoffs of the spoken word.

Like "infrastructural developments".

The minute listeners/viewers hear that kind of language, their brains mutiny and their attention shifts to which man has the better tie/haircut, or looks more comfortable.

Be clear, Taoiseach. I'm not suggesting you baby-talk the viewers. I'm telling you that if you don't make the end results of a policy interesting to viewers, you might as well not talk about the policy at all.

Remember, you're in someone's sitting room. You're not talking at a press conference to a cross-section of the general public. You're talking to one person who's had a tough day at the office. Or a couple, each of whom wants the other to put the kids to bed.

Neither of them is going to say "Ssshh, let's hear what he's saying" if you're talking billions, or the National Development Plan or any of the big conceptual issues you spend your life dealing with.

The definitive Big Debate is often assumed to have been the one between Kennedy and Nixon. In fact, a recent American example is much more relevant to your task next Thursday. The one between Al Gore and George W Bush. Before that debate, Gore led in the polls. After it, his ratings dropped like a stone. For good reasons. In the debate, he presented data. Used conceptual language. Set out to be impressive. The end result was that the viewers felt condescended to.

You don't have the kind of personality that would ever make viewers feel you're condescending to them, but you're still going to have to shift your point of view, your starting point, and work out how to interest tired, distracted people and make them remember a couple of points you made.

They sure as hell won't remember general guff about how far we've come. We know how far we've come.

And you know something? We're not that grateful. People's expectations move up all the time, and nobody votes out of gratitude. So please ditch the lists of achievements. Been there, heard that.

The other danger . . . and this is important . . . about talking history (even if it's recent history) is that it will push you into a deadly pattern.

That pattern will go like this:

1. You'll mention an achievement of the present government;

2. Enda or Miriam will go "Big deal, least you could do, took you long enough, never mind that, what about X?";

3. You'll get smilingly resigned to being unappreciated.

You showed smiling resignation during the Week in Politics RTE interview with Brian Dowling. "It's a funny old world, " you shrugged at the end of that conversation.

Smiling resignation is okay in a profile interview. It's not okay in a Big Debate, because the Big Debate is the equivalent of a job interview. You don't have to make like Michael McDowell's Energiser Bunny, but serene philosophical resignation is not the right gear for asking voters to put you in charge of their future.

By the way, unless Miriam pushes it at you, don't even mention the North.

Tony Blair said all you could ever want said about your work to bring peace. The other two events prior to Thursday will reinforce that. If you drag it into the debate (and I suspect you wouldn't, anyway), it'll sound like cheap credit-grabbing.

Finally, let me quote Somerset Maugham to you. He said that a writer's job was to make old things new, and new things familiar.

That's your job, next Thursday.

Dear Leader, THIS IS your first Big Debate, whereas the Taoiseach's done it before.

Problem? Not of itself.

The real problem is that because media people pay so much attention to the Big Debate, it can get separated from the continuum of the campaign and be seen as the definitive encounter. The qualifier or disqualifier. Which in turn makes political leaders feel they must play the part of a great prime minister, as opposed to being real.

You shouldn't get into that frame of mind. You shouldn't be reaching for an artificially elevated version of yourself. You shouldn't be ignoring your own strengths. You shouldn't be digging into the gravitas bucket or seeking to be specially statesmanlike.

If you do, you will iron yourself flat.

The way the format of Leader's Questions in the Dail has always ironed you flat. It forces you to be grave and punitive. Po-faced, even. So people were quite surprised when the election was called and the po-faced aspect of you disappeared.

Once the campaign started, you had a chance to show other facets of your personality. Enthusiasm. Energy.

Uncomplicated zest for people: every crowd has a silver lining, as far as you're concerned.

You will lose that at your peril in the Big Debate. No, I don't mean you should paste a smile over the nervousness I hope you'll feel. Or tell jokes.

But you do need to be enthusiastic and positive. More to the point, you need to do what you do when you're not ironed flat by the protocols of formal communication: tell stories, give examples, show the human implications of the issues you're addressing.

Above all, don't approach this debate as if it was an oral exam and you had to prove you know everything about everything. No politician ever did well on TV by proving themselves a polymath, but several have become pains-in-the-arse by trying.

Nor has any political leader drawn voters by articulating generalities.

Get specific and singular. You'll be helped in this by Miriam O'Callaghan, who hates wide-blue-yonder general statements. She doesn't want to know the what. She wants to know the how.

And the when. And where the money is going to come from. And why we should believe any of the above. Don't force her to tin-open those details out of you. Offer them.

You'll notice that I haven't concentrated on warnings. Warnings . . . and 'don'ts' . . . guarantee paralysis.

Because you and your party are doing better than had been predicted, you're going to be under hellish pressure not to blow it in the debate. You'll be up to your armpits in 'don'ts'. Don't do this. Don't say that.

Did you ever see Robert Redford's movie The Candidate? Redford played a politician who was candid. Straightfoward. Real. This attracted voters, and he had a real chance of becoming a senator. Except that once it became clear he did have a chance, his advisers started in with the 'don'ts', urging him to be more cautious, more proper, more circumspect, thus excising the only advantage he had.

It's a bit like the old pink elephant trick, where someone tells you not to think about a pink elephant. Suddenly, you can't think of anything but pink elephants. The 'don'ts' have the same effect: they focus you where you don't want to go. If you set out to handle the Big Debate determined not to do a bunch of things, you'll be bland, mundane, lifeless.

Nor am I giving you that idiot advice "Just be yourself." Each of us has dozens of different 'selves'. I'm suggesting you pick the best of yourself.

Let me give you an example. Twice in the past week, you refused to go where the person you were talking to wanted you to go. The first time it was about legislating for abortion. The second time it was giving the date by which you'd have fixed stamp duty. A radio reporter commented that by absolutely refusing to do what the questioner wanted you to do, but explaining forcefully why you wouldn't do it, you'd probably gained her vote. It was an example of Edmund Burke's principle that: "Your representative owes you not his industry only, but his judgement; and he betrays, instead of serving you, if he sacrifices it to your opinion."

The other aspect of yourself . . . the one that has surprised the hell out of a lot of people, including some of your colleagues . . . is the energy and stamina you've brought to the campaign.

You've run it as if your life depended on it.

But you know that neither your life nor your happiness actually depends on it. If Fine Gael doesn't do well and you lose the leadership, you will be as happy the following day as you are today.

That gives you a great freedom next Thursday.