I second the thanks for the reply, Thill. I just follow the instructions that came with my first Do-It mold, that I got as a birthday present in December, that recommended to oil the hinge at least once every pouring session, and to let the mold cool and re-oil it if the oil smokes. But you've obviously poured a heluva lot more jigs than I have, so who am I to say?
I use 3-in-1 oil, never even heard of 2-in-1 before. The 3-in-1 does smoke a little if the mold is real hot.