An example will make the nature of the straddle clear.
With an effort, she managed to straddle the vehicle behind him.
A " straddle " is a speculation on the difference between the prices of nearer and more distant futures, which varies from time to time, or on the difference between the prices of different kinds of cotton.
Praevaricare meant literally to walk with the legs very wide apart, to straddle, hence to walk crookedly, to stray from the direct road, varicus, straddling, being derived from varus, bow-legged, a word which has been connected etymologically with German quer, transverse, across, and English "queer."
She couldn't bear the thought of him returning to the troubled teen he'd been and tried to think of something to say to straddle the line between mothering him and letting him be his own person.