A quick pitch and an England team rediscovering their white-ball swagger, up against a demoralised West Indies bowling attack, proved to be an heady cocktail for the Southampton crowd as they lapped up an evening of audacious run-scoring.England's openers bristled with intent from the get-go, as the right-left hand combination of Smith and Duckett wreaked havoc.Duckett liberally sprinkled runs to all angles, with his innings full of nifty reverse sweeps, deft cuts and clever scoops. Alzarri Joseph stuck a paw out to a brutal Duckett drive on the up when he was on 37, but such was the ferocity of the strike it still flew to the boundary leaving the West Indies quick with a bruise but nothing more.Six overs in, England were 83-0 and it already felt the like the match was over as a contest as the shoulders of those wearing maroon started to droop.The diminutive Duckett dovetailed well with the taller Smith, as West Indies' attack struggled to find the right length against England's innovative strokeplay.Thrust up the order by Brendon McCullum to open in place of Phil Salt, who is absent on paternity leave, Smith has taken to the role like the manor born as he used his levers to good effect.Three consecutive sixes spanked off the bowling of Gudakesh Motie will have had the England coach purring before Smith dropped one inside the ropes to the biggest boundary and into the hands of Shimron Hetmyer. A century beckoned for Duckett, and the opportunity to join Jos Buttler and Dawid Malan as one of only three English players with hundreds in all three formats.However, the 30-year-old misjudged a sweep and was bowled behind his legs by left-arm spinner Akeal Hosein with the milestone tantalisingly within his grasp. Duckett thumped his pad with his bat in frustration.It briefly took the sting out of England's assault before Brook and Bethell played yet more eye-catching strokes en route to an imposing total.If England were ruthless West Indies were rudderless as this match marked the end of a pretty chastening tour.A 3-0 drubbing in the one-day international series was followed up by the same scoreline in the three T20s which have followed.Indeed, this is the first time West Indies have been 'double' clean swept by England in both a ODI and T20 series since 2012.Here they were again cumbersome in the field and struggled to know how to contain England with the ball. Romario Shepherd's economy rate was 19 across two overs and Hosein, their most economical bowler, still went for 10.50 an over.Evin Lewis pumped Luke Wood's for six off the first ball of West Indies' innings, but there was an end-of-term feel to the early part of the chase.Certainly the callous disregard for anything tossed up by spinners Liam Dawson, Adil Rashid and Bethell early in the innings suggested some of their top order were already in the departure lounge.West Indies skipper Hope, and the man he succeeded in the form of Powell, at least showed some fight during what always looked to be a forlorn effort. It does not help their cause that one of their best players - and one of the best T20 batters in the world - has seemingly turned his back on them.Nicholas Pooran, who was not part of this tour, announced his retirement from international cricket on Monday at the age of 29 and has prioritised franchise paydays.With eight months to go until the World Cup in India and Sri Lanka there is much for West Indies coach Daren Sammy to ponder.