The generality of figurative meaning does not mean simultaneously intending the literal and figurative senses of a single expression. It means treating an established figurative expression as covering the relevant cases within its conventional scope.
«والعمل بعموم المجاز أولى عند أبي يوسف ومحمد»
Abu Yusuf and Muhammad give precedence to the general reach of the figurative sense.
In an oath about eating a particular food, for example, the customary scope of an expression may be wider than a narrowly literal reading. The disagreement concerns whether to stay with that narrower literal use or apply a recognized broader figurative use. Each case still depends on wording and convention.