The IRB are trialling a reduced engagement phase that will feature only three instead of four verbal commands. The All Blacks' opponents have all had a few months to practise engaging to the sequence of 'crouch, touch, set'.
The All Blacks, though, are effectively coming in cold, with Dane Coles the only New Zealander who has had significant game-time under the trial laws that were used in the ITM Cup but not in the Rugby Championship.
The change may appear trivial - not something with the potential to trip up the All Blacks, but they have certainly upped their preparation load so far in Edinburgh to improve their timing and execution.
They are definitely wary that what might appear a subtle change is actually much more, with the potential to upset their rhythm and hand their opponents, who have had longer to bed in, a handy advantage.
"We have obviously done a crash course on [the changed rules] in the last week," said All Black hooker Andrew Hore.
"Colesy [Dane Coles] and those boys who have played it all year have got quite good. The boys [we are playing against on tour] have had a few games to get used to it but, unfortunately, we have had none.
"There have been issues with a few reset scrums so whatever we can do to keep scrums a big part of the game - I'll be happy to try it out."
Making the All Blacks particularly wary are memories of their last visit to the UK when they conceded more than 20 scrum penalties in their Grand Slam tests.
Such an enormous penalty count was entirely out of odds with the rest of their season and made especially strange by the fact that nearly every penalty conceded in 2010 was on the opposition put-in.
When the All Blacks were hammered six times in the second half of their final game against Wales, then assistant coach Steve Hansen even suggested his side were seriously contemplating not pushing in scrums in 2011.
The furore died down but the scrum could easily become a central feature on this tour as the northern hemisphere sides all back themselves at the set-piece. They all see the scrum as a weapon and an integral component of the battle.
The All Black forwards spent much of their first outdoor training on Tuesday working the scrum and the forwards stayed behind on Wednesday for more specialist tuition.
- By Gregor Paul in Edinburgh
