/diy/ - Do It Yourself

Im doing a general labor job and the project manager himself was out in the site using a mag to float some mud. He was trying to teach me about magnesium chemical reaction with concrete. I did concrete for a year and i noticed that he hadnt stripped the coating off of the magnesium float and said that he wasnt using magnesium till he stripped the costing off his mag and he told me he did 15 years and you dont strip the outer coating off a mag
Im so confused bros. Which one of us is retarded?