So if the words are "precise and unambiguous" then you just formalistically apply the assigned plain meaning of the statute to the facts, and you should not care about or consider the justice or injustice or reasonableness of the result. This is what Lord Atkinson said in the House of Lords, in the case of Vacher:
If the language of a statute be plain, admitting of only one meaning, the Legislature must be taken to have meant and intended what it has plainly expressed, and whatever it has in clear terms enacted must be enforced though it should lead to absurd or mischievous results. If the language of this subsection be not controlled by some of the other provisions of the statute, it must, since its language is plain and unambiguous, be enforced, and your lordships' House sitting judicially is not concerned with the question whether the policy it embodies is wise or unwise, or whether it leads to consequences just or unjust, beneficial or mischievous."
Professor Zander, in The Law Making Process notes at 39:
The most rigorous expression of it was Lord Halsbury's statement in Hilder v. Dexter  that the draftsman of a statute was the worst person in the world to interpret a statute because he was unconsciously influenced by what he meant rather than by what he had said. He had himself drafted the statute in that case and refused to give judgment on the ground that he might not fully appreciate the literal, objective meaning of the words he had used. One of the chief reasons for this approach was said to be the length of legislation by comparison with former times. In l840 Lord Brougham said: