McCullum played the game today, indeed New Zealand fielded an unchanged XI from that which won the first T20 by 12 runs under the Duckworth Lewis method 24 hours earlier.
"Kane will learn a lot from it. It's another of those areas we need to make sure we have cover come World Cup time," Hesson said.
Hesson admitted the West Indies were well worth the win today, having made 165 for six, then bowling impressively to restrict New Zealand to 126, the final wicket falling with five balls left.
Andre Fletcher's 62 off 49 balls put down a foundation for the hosts and others chipped in. New Zealand's bowling wasn't good enough through the middle stages, although Trent Boult pulled off another spectacular one-handed catch in the deep to dismiss big-hitting Kieron Pollard.
Apart from Williamson's 37 off 28 balls, none of the other batsmen were around long enough to anchor the chase.
They were reminded of the skills of finger spinner Sunil Narine, who once again flummoxed the batsmen, and might have had them wondering how much he might have affected the test series outcome, had he not been a victim of West Indies cricket politics and left out of the squad.
"We didn't want to finish on a loss but overall it's been a great tour for us. We came over a couple of years ago and got turned over. The fact we won a series away from home is a big achievement for us," Hesson added.
New Zealand have a break from international cricket until South Africa come out for three ODIs in late October, followed by a test and limited-overs series against Pakistan in the United Arab Emirates in November.
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