Sorry to sound negative but WHY would you squirt any type of oil etc. onto a boot to aid break in. The whole theory of a boot being stiff is to keep ones ankle from being destroyed in a crash. Boots were never supposed to feel like wearing sandals. They did feel really really stiff for the first month. But when they get broken in they rock. So before you go out and destroy the functionality of your boots do yourself and your ankles a favor and break them in the old fashion way. Wear them around the house and enjoy the pain while watching football or eating dinner!!!!!