Yesterday, though, as he made his statement on the bombing of Iraq, the accuracy of his transmission wasn't quite up to its usual standards - seven or eight times there was a mispronunciation or slur, or a tiny hesitation which wasn't part of the familiar halting rhythm he adopts when the occasion calls for high seriousness.
I wouldn't want to suggest that these were structural cracks in the facade of deliberated resolve which the Prime Minister wanted to present - there was absolutely no prospect of a large slab of statesmanlike purpose sheering off, to reveal a jerry-built construct beneath - not least because almost every MP present was at pains not to lean too heavily against the plasterwork. But these little vocal glitches were evidence that the structure was under pressure, microscopic stress fractures testifying to the considerable load that was bearing down on the speaker.
As I say, the burden wasn't that of parliamentary scrutiny. "As I speak, British Tornado aircraft are engaged in action," Mr Blair had said near the beginning of his statement, and he must have known as he did so that he was triggering a sensitive reflex - one that continued to twitch in the questions and debate that followed, as speaker after speaker made the required genuflection to our brave men and women. This was just jaw- jaw, but out there somewhere acts of war were taking place and the instinct of solidarity could be relied on.
Nor was Mr Blair worried about the stray rounds from his backbenches - "friendly fire" you could call it, if anything remotely like amity could be detected in the seething indignation of George Galloway and Tony Benn. Those he could dismiss with a kind of baffled bemusement.
When Mr Galloway passionately denounced "a new crusade, led not by Richard the Lionheart but by Clinton the Liar", Mr Blair rose and shook his head. "I find it - well, to be honest I get beyond anger," he said resignedly, before pointing out how perverse it was to attack the American President while offering not a word of condemnation of Saddam Hussein.
But what was really putting the pressure on Mr Blair, I think, were the remaining splinters of the doubt he must have entertained at some time. He had the demeanour of a man who had convinced himself, but was happy to hear the arguments once more, to hear himself frame them out loud and hear a murmur of assent from his audience. If that was the case he got what he wanted, from a House that had clearly decided the moment for debate had passed and had little remaining patience for the only true raison d'etre of the chamber - dissenting voices.
The bravery of British airmen was invoked repeatedly, with a faintly distasteful glibness, but the courage in the chamber came from those kamikaze backbenchers who took off in the face of insuperable odds. They were fighting on the wrong side and were poignantly vulnerable to even the lightest fire: Tony Benn, engines screaming as he zeroed in on the aircraft carrier Western Hypocrisy, stuttered off course after Christopher Leslie had intervened to ask him what alternative course of action he would suggest. But, even if you think them mad or bad, there was something impressive about the determination with which they went down blazing.