Their problem is that the same blanket would struggle to cover the St Peter's tight five. The visiting forwards get hold of Grammar's expertly assembled maul, hurl it over the touchline, and it becomes obvious that for one of these teams today is going to be all about damage limitation.
Grammar play all the rugby, and Sky's fulltime stats prove it: Grammar 63 per cent possession. Grammar 81 rucks and mauls, St Peter's 17. Grammar 22 pick and drives, St Peter's 2. Grammar take the ball through seven phases five times, St Peter's 0. But who needs phases when you have this kind of size advantage? St Peter's score five tries, and four of them come from first phase set-piece ball. They simply target the Grammar first-five channel and bust through it.
When Grammar have the ball and their five-eighths, James Copeland, takes the ball to the line he gets tossed around like a rag doll. He's replaced shortly after halftime by outsize winger Braxton Stanley. Stanley may not have the vision of a traditional first five, but today that doesn't seem relevant. The final score is St Peter's 29, Grammar 7.
"WOULD I have been an All Black if I hadn't gone to Auckland Grammar?" Grant Fox ponders. "I think not. There was an incredibly high standard, high expectation of excellence, it didn't matter whether it was academic or sport.
"There was an environment provided and a lot of leadership expertise went into creating that environment. There was a legacy that you were expected to do your best to uphold. If I'd have gone to the local high school I really think there's a chance it wouldn't have happened, so I've got a lot to thank Grammar for."
Fox played for the Grammar 1st XV during the golden period. Under Graham Henry, their coach from 1975 until 1980, they at one point won 46 consecutive games.
The fact that the school has produced 51 All Blacks - the next highest is Christchurch Boys with 41 - suggests that historically this is New Zealand's most successful rugby school. Recently, however, the most famous 1st XV in the country has fallen on hard times. The "perennial champions" tag is gone.
In terms of Auckland 1A championships, the decade 2000-09 was the least successful in the school's history. (They still won four.) The last time Grammar were national secondary school champions was 1992.
The reasons behind this decline are socio-economic: the development of Auckland in the last 20 years has seen Grammar's catchment area become populated with a far higher percentage of Asian families than was previously the case. This shift in the landscape was then thrown into sharp relief in 1999 when strict zoning laws were introduced, putting an end to Grammar's ability to select students from other less-affluent parts of Auckland. (Two of the school's most recent All Blacks, Doug Howlett and Ben Atiga, were both out-of-zone students). The Maori and Pacific Island population of the school, which was about 10 per cent in the early 1990s, had by 2009 dropped to 3.5 per cent. In 2002, headmaster John Morris admitted that "if we didn't accept siblings there would be virtually no Maori or Pacific Island students".
Ben Skeen is master in charge of rugby at Grammar, and he's aware of the challenge. "The reality of zoning is that we are getting a lot more boys living in the zone who aren't rugby stock. Aren't what we would generally term the rugby, racing and beer community. If you look down at our weight-restricted grades last year we had five teams in finals, so there we've continued to be successful. But we've struggled at open-grade rugby. That's a reflection of what's on the school yard, you walk around and a lot of the boys are not big boys."
Grant Hansen, director of sport and a former 1st XV coach, agrees. "It's not really a rugby population. Our Asian boys were generally born and grew up here, so they're pretty immersed in rugby, but at the top end they don't produce the big physiques, the 1st XV physiques. If you go to a school like DeLaSalle in South Auckland you could probably find a whole raft of players who are huge and props, but at Grammar we have to manufacture them out of other positions. When I had the 1st XV in the late 90s we had some big units. We had 130kg props, [2m] locks, our average size was over 100kg. But since 2000 we haven't really had that."
Grammar is an impressive - and intimidating - place. It feels like I'm in a corridor of power, and Skeen confirms that the situation is a high-pressure one. "Our stakeholders - our old boys, our community - don't expect us to operate in cycles, they expect us to be there every year. The public face of Auckland Grammar school is our 1st XV.
"The headmaster travels around the world and meets the old boys' network in places like London and Melbourne, and the first question is often, 'How's the first XV?"'
The Grammar Old Boys provide both financial help - $450,000 towards the new pavilion was raised in one night - and coaching expertise. According to Hansen, "Ben [Skeen] and I could make two or three calls and we'd have six All Blacks coaching on the sidelines just like that, even if their sons don't go to Grammar."
Skeen wants to ramp up the Old Boys' involvement. "If we can get those guys back in to the school then with their expertise we can say, 'We'll play a faster game, we'll be smarter, kick off both feet, play territory instead of combative channel-one rugby, and we'll get game success ultimately.' So that's the challenge at the moment, to continue to think of better ways to do things."
If the provision of high-end paraphernalia was a guarantee of 1st XV success, Grammar wouldn't have a problem. There's a deal with Mizone, the sports-drink company, and in the lobby of the gymnasium we pass a stand displaying New Balance footwear, presumably for sale to students.
When I step inside the gym it suddenly feels like I'm breathing air meant for elite athletes. It's the kind of cavernous, air-conditioned space that I would expect to find in London's Olympic village. The summer training squad is spread out in front of us, undergoing an exacting Pilates-based workout. I follow Skeen up to a viewing platform where we join the rest of the rugby committee: Hansen and 1st XV coach, Irishman Ali Patterson.
Patterson has his eye on a gangly kid who is the tallest of the boys on show, but whose lack of co-ordination marks him out as a graduate of the English school of physical education. This is the boy's first year at Grammar and Patterson is wondering if his passing and catching can be brought up to standard in time to give him a shot at the 1st XV, where presumably his height could be used as a source of possession. If Grammar are to have any hope against bigger opponents, they're going to need the ball. Ideally their lock forwards would be ball carriers and creators as well as lineout jumpers, but as I scan the students below us I can see that being a Grammar coach these days means inventing a few workarounds.
The conundrum that has faced the school since zoning was introduced isn't going to go away. Fox grew up on a farm in the Waikato before becoming a boarder at Grammar in his teens, but his particular pathway no longer exists. "When I was in the 1st XV at Grammar, 11 of us were boarders. I have an issue with the new zoning rules because it's not the real world. The real world is fiercely competitive, and rules like these disadvantage kids who are genuinely wanting to move to further their academic and sporting opportunities. The levelling of the playing field promotes mediocrity, not excellence."
Manoj Daji, CEO of Auckland College Sport, disagrees. "We're not anti-competitive. The Auckland 1A competition is now pretty hard to pick. You show me a good sporting competition that doesn't have some restrictions in place to protect an even playing field, to create for its customers a competition worth watching, where one or two teams don't just dominate all the time."
He feels there's a perspective that often gets buried beneath the rhetoric of the zoning debate. "What about the child who is about to graduate to the 1st XV and suddenly sees his place go to a child poached from another school? It has a big effect on someone's life when that happens, often they'll get turned off the sport and walk away."
I leave the gates of Grammar and wander down Mountain Rd, past immense colonial mansions. For sure there are other, less-obviously moneyed parts of the Grammar "zone" but the paradox is clear: the school with unparalleled resources whose flagship 1st XV have just lost their most recent game 46-0.
* Adrian Hyland is a freelance writer who divides his time between Britain and his native New Zealand.