The West Indies players were clueless against Shamsi. But at the same time, his version of spin may be less effective against sub-continent teams such as India, Pakistan and Bangladesh.
Lets see how he will play against sub continent batsman, West Indies batsman used to play well against spinners and if he is able to trouble them then they could trouble other batsman with their line and length.
The win over West Indies will boost the morale of South Africa. I was expecting a relatively easy series win by West Indies, because they are so good in this format. And West Indies had fielded a full strength side - Kieron Pollard, Andre Russell, Nicholas Pooran, Dwayne Bravo, Chris Gayle, Evin Lewis.etc. Still the Proteas managed to win.
After watching the first match, i thought West Indies would win the series even thought it might be close matches because they have a really strong team but they failed to perform as a team during crucial times and and props should be given to the team to compose everything fast and perform well.