SWEET,
easy to be taken in; Also expert, dexterous, clever: As, Sweet's your Hand; said of one who has the Knack of stealing by Sleight of Hand.
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Entry taken from 1736 Canting Dictionary, by Nathan Bailey.
Sweet in the 1811 Vulgar Tongue
Also see examples in Canting Songs and Slang Rhymes collected by John S. Farmer (1896).