I was walking with my friend and when he went to take the lift to ground floor from the third floor, I suggested to him, "Let's at least climb down the stairs"; the word down taking some extra stress, meaning that since it is easy to run down the stairs, let us at least do that.
But he corrected that climb down cannot be used in a grammatically correct sentence. Is it true?
I always thought, climb up is a phrase that means to go up; similarly, I conveniently assumed that climb down is also a possible phrase that means to go down something.
Please clarify.