I'm pretty sure you do not want to boil leather if you want to use it as armour. Although if you boil it long enough, it'll become sort of edible.

Nitpicking aside, anything is better than nothing and leather isn't half bad as "cheap and cheerful" armour goes. It won't stop a strong direct hit of course, but it'll stop lesser hits that would be incapaciating without such protection - and all things considered it's light and cheap.