How do you measure McCullum?
A man stands in a conference room. He is a bundle of energy, as always. This time that energy is about to start a Powerpoint display. One that, he hopes, will let him get his dream job and fulfil one of his greatest ambitions.
Powerpoint presentations are not simple. You need the right cord, a Microsoft brain to understand the program, remember where you saved the file, work out your text, make sure you don't double-click, time your segments, make eye contact, prove you are a worthy candidate, and ensure you deliver the best and most important speech of your life while a group of people judge you as they look over your shoulder to your chosen professional-sounding words in Helvetica Bold: "Unit". "Desire". "Key performance indicators".
Brendon McCullum gave it his all. Maybe there were mistakes, maybe it wasn't perfect. Maybe it was, like most of what he did, the best and worst of everything he had.
When it was over, the job was not his.
But McCullum kept fighting for it. He almost imploded New Zealand cricket to get it. Instead of computer slides, it was desperate slides. Instead of programmed knowledge, it was untameable carnage. It was McCullum doing what he was born to do: give it everything on a cricket field. McCullum doesn't fit into spreadsheets or algorithms, he cannot be labelled or given the appropriate metadata.
Brendon McCullum is a night out on the town in Manchester. He is a sawn-off shotgun. He is gangsta rap. A giant butterfly of destruction. A cyclone made of laughter. He is bigger that the sum of his parts, of the sum of his results. He is something that shouldn't work, that shouldn't exist, something that crashes into things, through things. He is a smile of pure joy, a disgusted shake of the head, the last dying breath of Henry Ford, Frida Kahlo's paint, Sid Vicious' hair, James Brown's "huh". He can do anything, and nothing, all at that the same exact moment.
If X factor was an actual thing, not just something people said when they couldn't articulate someone's skill, not just something that replaces real words that mean something, not just a buzzword invented by dullards, Brendon McCullum would be richer than Bill Gates by just selling his own blood.
Much like X Factor, many have debated what makes good captaincy. There are those who try to pin down what a captain adds to a side. They will talk about how fielding changes percentages, how mistakes at the toss and batting order barely change the outcome of a match at all. But you can't put what most captains do on a spreadsheet.
When Mike Brearley took over from Ian Botham in '81, and Botham became Botham again, it is pointed to as a masterstroke of captaincy by some, and dumb luck by others. How much credit should Brearley get? Did he calm Botham? Did he inspire Botham? Or was it just the captaincy being taken away from Botham that really changed things?
We don't know. Statsguru can't tell us this. Even Brearley and Botham can't really tell us this. Some things are immeasurable.
Is the captain who risks a short leg better than the captain who turns a potential player into a star in the change room? Who could ever know?
How can we factor in the butterfly effect of what one extra slip does to a game of cricket? The batsman might play differently if he isn't there. The bowler might bowl differently if he is there. The slip might drop the catch anyway. That one slip is many things.
McCullum seemed to have a million slips. His fields were funkier than Funkadelic. And it looked like his men played better for him than they had ever played for anyone else.
Like most things Brendon McCullum, it's immeasurable.
But the wins came more than they had before. With two seam bowlers who have averages of just over and just under 30; perhaps his most naturally gifted batsman playing out his career in county cricket; no long-term opening pairing; and a random collection of working-class spin options, New Zealand had one of their best periods ever.
And McCullum did something even more remarkable than that. He demanded his country's interest. He was like a general taking on rugby union in their territory, and he changed the way New Zealand played and thought about cricket while he was at it.
This was a team, a nation, that played cricket the same kind of way almost throughout their history. They may have had Sutcliffe, Reid, Hadlee, Crowe and Cairns giving them flair. But as a team, they were more Turner, Fleming, Vettori, Coney and Chatfield. Smart, earnest, hard-working, and kinda boring.
There was not a single moment under McCullum's reign that his side were boring. They were box office. Things went bang. There was a love interest. They had to fight the big fight, the opposition always seemed bigger. They ultimately didn't get what they wanted. But along that journey, they changed as a cricket side. He changed them.
How many captains in the history of the game can say they changed how their nation played, and perhaps thought of cricket? He wasn't captain of New Zealand. He was Captain New Zealand.
It wasn't just New Zealand. From the minute he opened Lalit Modi's IPL, to when the Australian newspapers all but tried to claim him as an Aussie, McCullum had been living large in a Big Three world.
Perhaps it was most obvious when Sky were so captivated by Brendon McCullum last summer that they all but strapped him to a gurney and cut open his scalp just to see how his brain worked. Instead, they let Nick Knight interview him with a Subbuteo Test Cricket set in front of him.
Knight's questions were in black and white, McCullum's answers were in colour. Knight wanted to know what field McCullum would set to start an ODI innings. McCullum wanted to know all the variables, the pitch, what ground, did it swing, who was the batsman, everything. You couldn't ask him one question and unlock what he did. His brain was like his batting, it was in a never-ending state of cricket mania.
Not that he was the first New Zealand leader to have a cult following. Jeremy Coney even looks like a cult leader with his turtleneck sweaters, and he sounds like one with his dramatic thespianic mid-quip abeyances. There are many who pray at the altar of Stephen Fleming. And Martin Crowe was one of the seven wonders of the '80s.
McCullum is like all of them, combined. His following went from cult to worldwide. In a universe that includes AB de Villiers, Chris Gayle, Dale Steyn, Kumar Sangakkara. McCullum could often claim to be the world's favourite cricketer.
This was a wicketkeeper who spent much of his Test career averaging in the 30s. This from a batsman who struggled to make runs against any real teams. This from an Andy Warhol 15-minutes-of-fame player.
It didn't matter how short it was, though. You can't unsee McCullum bat. His innings leave an imprint. You remember how it felt to watch them. The danger to him, the danger to bowlers, the danger to the crowd. Him outside leg stump, down the pitch, using his bat like he is trying to behead an invisible monster sent here to kill us all.
What was amazing was, he managed to capture that lightning, magic, madness, and used it to lead men.
McCullum led like he batted. For better, almost the entire World Cup; for worse, the last match of the World Cup. Stupid, dangerous, breathtaking, visceral and unmissable. It was like watching a Tasmanian devil try to bring down an elephant. If he did do it, you were completely amazed; if he didn't, you thought he was foolish to even try. Ultimately his entire leadership career was like most of his innings: so much fun, way too short.
Brendon McCullum has never won a World Cup. Or a World T20. Or even a Champions Trophy. His team has never been the No. 1 team in Tests. He hasn't made 10,000 Test runs. He didn't revolutionise modern wicketkeeping. His biggest moment was actually losing a World Cup, within an over. His team wasn't one of the greats. He isn't one of the greats of all time.
There are many things he wasn't. What he was, well, that was immeasurable.
How do you measure the excitement you felt when he was captaining a team, when he was flying through the air to save a boundary, or those special, unforgettable, exciting moments when he was tapping his bat, about to face a ball?
A man stands at the crease. He is a bundle of energy, as always. This time that energy is about to hit a cricket ball. One that, he hopes, will go to the boundary.
Brendon McCullum gives it his all. Maybe there are mistakes, maybe it isn't perfect. Maybe it is, like most of what he did, the best and worst of everything he had.
When it is over, cricket will miss him.
Jarrod Kimber is a writer for ESPNcricinfo. @ajarrodkimber