One of the Italian scores against the Springboks on Saturday was the result of centre Adrian Jacobs being in the wrong place. In the end the mistake was forgotten because we won 32-10, but in another match it could have been the difference between defeat and victory.
The rugby media often talk of Jacobs' "defensive frailties" - one of those terms that tends to stick - as if he is reluctant or unable to tackle. Of course there is no position where a player's tackling (or lack of it) is more exposed than centre.
John Smit Hooker, not prop or kicker
It is also true that the centre sometimes has to take the fall for work that has not been done by those in front of him.But Jacobs, though he is relatively small for a back (and a midget in the team as a whole), has often shown he is neither afraid nor incapable of tackling. The "frailty" is more accurately a reference to his defensive alignment - in other words, what he has to do before he has to tackle.
That in turn depends partly on the partnership between the backs. The Bok backline has been disrupted with the departure of Jean de Villiers and Frans Steyn, and new combinations take time to settle.
The same applies to the front row, where the strength, aggression and technique of the three individuals can really only be fully exploited when they know each other well. Rugby legend is populated with legendary front rows which had the luck to be able to stay intact over many matches, even many years.
In Wales they still talk about the Pontypool front row of the 1970s (listen to the hilarious standup routines of comedian Max Boyce). In Pretoria most fans could name the Bulls' enduring 1980s front row without thinking - Jan Lock, Uli Schmidt and Heinrich Rodgers.
The value of these settled combinations was often recognised by national selectors. As in rowing, the combination is more important than the individual talents.
The Springbok front row has had too many changes on this unsuccessful tour of England, France, Italy and Ireland. None of the combinations has had time to settle, and in one case - the match against Saracens - the individual experience was also lacking.
Perhaps it is time to move John Smit back to hooker, regardless of his unselfish readiness to play prop. Certainly the scrum looks more solid when he is at number two. The recall (apparently from Durban beach) of BJ Botha to an injury-stricken touring side reminds us that there was nothing wrong with his propping in the first place, and he should have been retained.
It may be that the decisive flaw in the approach of coach Peter de Villiers is his tendency to play men out of position, or not to allocate them a permanent position in the first place. Frans Steyn, Ruan Pienaar, Smit - all seem lesser players than they were.
Against Ireland, expect the Boks again to look unsettled and therefore to be easily disrupted. In defeat we look to blame individuals, when often we should be looking at the combinations.