Sentence:  This much she knew her mother to be aiming for, motivated by a need to escape the fate and the malice of women like Maud, a need to arrange matters by her own <WSD>light-handed</WSD>, cool-hearted expertise so that when High Grange did become the property of Francis, or another, she would be in a position to laugh as she took her leave, driving off in her own carriage to pleasures of her own choosing, in her own home. 
Meaning of the word marked with <WSD> tags:  Delicate and skilled; nimble and dextrous