Wynne Gray: What's the point of a two-minute substitution?

Hauling Perenara off at the death and asking Pulu to run on for a glorified warm-up session does not dignify the All Black jersey. Photo / Getty

Augustine Pulu has two All Black caps.

He got an introductory taste about life near the top level when he replaced injured Chiefs teammate Sonny Bill Williams for 20 minutes against USA.

His second appearance came in the last two minutes of the test against Scotland, a cap he will gather without any differentiation from captain Richie McCaw who played throughout his 136th test.

It's a ridiculous system on several levels. What did the All Black coaches learn about Pulu's play in that drive-by appearance and how could he make any substantial contribution? He biffed a pass to no one which was unsurprising given the volume of inaccurate work from his colleagues in the rest of the test, barely broke a sweat then shook hands with the Scots.

If the coaches want to learn about their men and how they respond to pressure and match circumstances, what's wrong with a good hour to assess TJ Perenara before giving Pulu time to settle and close out the game.

Replacing Perenara would have made sense if he was injured. The coaches will say they had used the rest of their bench early and had to save Pulu in case of a late injury.

Did Malakai Fekitoa and Daniel Carter both need replacements (Sonny Bill Williams and Julian Savea) whose qualities are well-known to the coaches? That jammed the door shut on Pulu getting some reasonable time on the field to put up his credentials in the blurred field of deputy candidates behind Aaron Smith.

That will happen. Using substitutes is not an exact science although many coaches appear to work on a preordained script when they make changes around the hour mark.

Hauling Perenara off at the death and asking Pulu to run on for a glorified warm-up session does not dignify the All Black jersey. Many would argue there was a lack of players at Murrayfield who produced performances to honour the famous strip.

Perhaps historians who chronicle All Black records and those who administer the game in New Zealand might start thinking about an asterisk for Pulu's comet-like appearance.

He was not an injury replacement or a tactical substitute. He was a laundry bill and even then he barely justified any detergent.