Formation strength testing
Limit or leak-off tests in development wells may be omitted if no hydrocarbon bearing and/or overpressured formations are to be penetrated. Information obtained from leak-off tests in straight holes is not applicable to deviated holes in the same field (and vice versa). Only measurements in the deviated hole themselves should be used.
It is not necessarily true that deeper horizons always have a higher strength than shallower ones. If less competent formations have been drilled through, another test can be made immediately upon penetrating a transition zone or a cap rock . . .