Also, and especially in the physical sciences—“Other techniques for achieving similar goals include...” or “A complementary measurement of the same quantity...” In these cases knowing what they’re doing/trying to do is sufficient.
Of course, the more relevant it is, the more important it is to actually read it. By the time you get to things that you claim actually support your argument, you had better have read them several times carefully.
Also, and especially in the physical sciences—“Other techniques for achieving similar goals include...” or “A complementary measurement of the same quantity...” In these cases knowing what they’re doing/trying to do is sufficient.
Of course, the more relevant it is, the more important it is to actually read it. By the time you get to things that you claim actually support your argument, you had better have read them several times carefully.