Bottom line - there hasn't been a natural tactical director since Spencer left. Now they have one. Hall can be the general they need. He has become a critical part of the Blues machinery in 2014. The 22-year-old has regularly been the momentum-changer, the player who has most often best assessed the right places to attack.
He has shown a natural awareness of where the space might be and a willingness and ability to probe through different means to exploit it. And, vital in any playmakers' repertoire, he exudes calmness under pressure. Hall is the player the Blues have been chasing for a decade, it's just that he pulls the strings while wearing No 9.
This is a little strange in New Zealand but common in other countries, most notably France. The French have always viewed the halfback as the beating heart of any side.
Jacques Fouroux, Pierre Berbezier, Fabien Galthie . . . great players who steered great French teams. So how does Hall feel about being a French-style halfback general?
How would he feel being asked next season to be the man who sets the tempo and rhythm for the Blues?
"I'd be very happy about that," he says. "But we have some awesome senior leaders here as well who I talk to a lot. If that eventuated, I would enjoy that responsibility. I did it at school and New Zealand under-20s as well, and having that added responsibility is quite nice."
It helps that Hall has had a fair bit of experience playing first-five. A former pupil at St Peter's College, he found himself wearing No 10 a few times while captain of the first XV.
It was a position he felt an affinity for and, with an excellent passing game, a solid kicking portfolio off either foot and a bit of pace off the mark, he went OK at it, he reckons. The more Hall has played this year, the more his natural game has come out and the more he's been able to show his ability to steer the Blues.
"I guess being in the saddle a bit longer, you feel you have that sort of responsibility," he says. "Guys know you, so they can trust you.The main people I go to [to discuss strategy during a game] are the first-five and Ma'a Nonu-he sees a lot of what is going on. So the pictures I am seeing on the field, I will bring themu p to Ma'a and Ihaia [West] and I feel a lot more confident about approaching them and saying what I think we should be doing."
Hall is about as surprised as everyone else that this season has worked out the way it has. This time last year, his was a name barely known outside the franchise and, by the time the campaign finished, he'd have been reminding a few team-mates about who he was.
He arrived at the Blues as the third-ranked halfback and then broke his jaw playing club rugby. To compound matters, he caught glandular fever.There was a danger he'd never be seen again - contracted for two seasons, the Blues had the option to de-list him.
It's not that the coaching staff had lost faith in him but he didn't have any form and, with Benji Marshall and Nonu both coming to Auckland, there had to be some players squeezed out of the mix.
Could the Blues have coped with two halfbacks? That was a question Hall knew the coaches might be asking and, once given the all clear to play for North Harbour in the ITM Cup, he had to provide his franchise with reasons to keep him.
"We had two quality halfbacks in Piri [Weepu], and Jamo [Jamieson Gibson-Park] was making pretty big strides with Taranaki and New Zealand Maori," says Hall. "I knew I had to be on top of my game and be prepared mentally and physically. I believed those two were ahead of me and that thought was always with me.
"You don't get many opportunities at this level, so I knew I had to take my opportunity in the ITM Cup [last year]. I asked the [Blues] coaches what I needed to work on at North Harbour and I did that.
"When I came back into the Blues for pre-season, I hoped I would get an opportunity and I was fortunate Piri went down. That was unfortunate for him but I played not too bad in those few weeks."
Not too bad is under-selling himself somewhat. He has surpassed Weepu now and left him facing a future of cameo benchwork. In a straight choice between Weepu and Hall, the Blues would pick the latter every time now. The younger man is the future, the aerobically charged, dynamic athlete the role demands.
