Matt Roller is an assistant editor at ESPNcricinfo. @mroller98
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But the fundamental question underpinning that discussion is one that captains, coaches, analysts and strategists consider every time they pick a T20 team or squad: should your best player bat in the most difficult position, or the one that allows them to face the most balls?
Ed Smith, England's selector between 2018 and 2021, has a clear view. "T20 cricket is a game of restrictions," he writes in his new book, Making Decisions. "This is fundamental to understanding T20. Your best bowler is capped at using one-fifth of your resources. Your best batter is free to dominate the whole innings."
Smith was instrumental in England's decision to promote Buttler to open the batting in T20 internationals in June 2018, two months after his appointment and a matter of weeks after recalling him to the Test team. He had done so once before, against Sri Lanka in 2016, and had spent the previous two IPL seasons opening: first for Mumbai Indians, then for Rajasthan Royals.
He had been hugely successful in that role, making five half-centuries in six innings at the top of the order in the 2018 season, but it was not an obvious call. England had an established T20 opening pair in Alex Hales and Jason Roy, and promoting Buttler meant Hales was pushed down into the middle order. That forced Joe Root down the order in turn, and eventually out of the side altogether.
Smith tells ESPNcricinfo: "I always used to think that if you took England's 50-over team and the match was shortened to a T20 for whatever reason, that surely England would become more likely to win because of the destructive batsmanship in that side. And yet, we were ranked much higher in ODIs than in T20s. Therefore, I thought that potentially, we could set up in a more attacking way.
"The danger," he adds, "is that if you have remarkable batters down the order, they don't get a chance to shape the game. It seems to me a shame when a player is limited to a very small proportion of the match that they can influence, if you believe that player is an outlier or exceptional."
Smith put Buttler in that category. "The batting order in T20 is probably of the same level of significance itself," he argues. "Because you are effectively selecting which player has the potential to face which proportion of the total allocation of balls.
"It's effectively the size of the bet you're making: if you're asking someone to open the batting, you're obviously making a larger bet on their potential to influence the game." England went all-in on Buttler and doubled their money: since 2018, he averages 46.71 and strikes at 153.53 as a T20I opener.
"It's important to stress," Smith adds, "that I always believe the captain should decide the batting order. Technically, that decision resided with Eoin [Morgan], as it should do. But if you want to know what I argued then - and would argue now - then yes, I think Jos Buttler should open the batting for England."
The other facet of Smith's argument was technical, not tactical. "At the beginning of T20 in 2003, there was a school of thought that a T20 team would be ten bowling allrounders, who slog it a long way and a wicketkeeper. Well, we all know that isn't the way it worked out: actually, brilliant batsmanship has been elevated by T20.
"When I look at the very, very best white-ball opening batsmen, I see a pattern in their play: low-risk off-side touch play, combined with selective, on-side power-hitting. It's like Damien Martyn through the off side and then Andre Russell over long-on. Of course, what we're describing looks quite a lot like Jos Buttler and Rohit Sharma.
"They have that ability to hit good balls through the off-side field, playing relatively low-risk shots - and the fielding restrictions mean there are always gaps on the off side in the first six overs - and then when there's a mismatch, they have the potential to hit 22 or 24 runs off an over, playing higher-risk shots, often to the on side."
Smith notes a number of counter-arguments, which he describes as "recurring memes", in Making Decisions: "'Yes, he's the best player across the whole innings, but the gap between him and the next-best player is wider in the context of the end of the innings than at the beginning of the innings…' 'Yes, he's a great batter, but we don't want to use him high up in the order because we need him at the end to finish the match off…'"
But he is firm in his view that the best players should have access to as much of the innings as possible. "The case for superior players having access to maximum opportunity is rationally irresistible," he writes. "It's not much use having a brilliant batter finish off the match if it's already too late for him to finish it as a win."
How does Smith square his view with the fact that AB de Villiers - whom he observed first-hand when consulting for Royal Challengers Bangalore in 2016 - prefers batting in the middle order? "Players touched by genius have their own way of looking at the game," he says with a smile.
"It may be that he's so good that, in his head, he thinks 'if I'm not out, we're always going to win'. My own view is that I would want de Villiers to face as many balls as possible. If he went to No. 3, that's fine, but I wouldn't want him going much lower than that, personally."
His view shifts in the case of Andre Russell, who has opened in only two of his 367 T20 innings, and is best described as a hitter, rather than a batter. "I'm less sure there," he concedes. "My feeling is that he's uniquely well-suited to the latter stages. Buttler is a good example of the type of player who I'd be most reluctant to end up having seven or eight balls; Russell is slightly different, with his unbelievable power."
It is clear from Making Decisions that Smith does not believe England's selectors have received enough praise for their decision to double-down on ultra-aggression by promoting Buttler - one which he indirectly compares to Houston Rockets leading the NBA's three-point revolution and the success of Spain's footballers when playing without a recognised striker in their side from 2008-12.
"Once these strategies started to work, the debate simply shifted elsewhere, with sceptics becoming converts," Smith writes. "This trend is another injustice awaiting anyone who is in the business of generating new ideas. When the ideas don't succeed, they stick in everyone's memories. But when the ideas do succeed, they become self-evident."
His argument is best illustrated by the shift in stance from the man who chaired selection for England's T20 World Cup squad while recruiting for a new full-time selector, Rob Key. While working as a pundit for Sky Sports, Key was a strong advocate of Buttler returning to the middle order; as England's managing director, he has accepted that he is best used as an opener.
There is one thing missing from Buttler's CV as a T20 opener: victory in a final. Perhaps, if he can fire England to the World Cup in Australia over the next four weeks, Smith will belatedly get the credit he justifiably feels he deserves.
Making Decisions: Putting the Human Back in the Machine by Ed Smith is out now