You'll find a lot of advantage of oil into a hot pan over oil into a cold pan.
You won't smoke the oil as badly as often -- that means you won't have to deal with the bad flavor and the gooey mess after it cools down.
You'll use less oil. When it goes into a hot pan, it spreads really easily. You'll find yourself using a tsp where you used a tbs. The techniques of sear and saute are meant to be done with very little oil. Food will taste better.
The pan will release better. When the pan is already hot, the oil fills its pores better. Or something. I honestly don't know why it works, but it does. If you want to go for super-non-stick. Put some oil in a cold pan, heat it to warm. Dump it out, wipe the pan, put the pan back on the flame, heat it, then add the oil you want to cook with. Sort of an instant seasoning. But I'm getting ahead of myself. The "release point" is a very important point of sear and saute. You shouldn't have to use a spat to get things moving in your pan. It screws up the surface browning and screws up the fond.
Cooking with butter is a little different. Obviously you use more butter than you'd use oil because it tastes so good, also you control the pan to control the browning of the butter as opposed to the browning of the food. But... hint... Preheat the pan, take it off the flame, and add just a couple of drops of oil, swirl them, then add the butter still off the heat. You'll not only temper the pan, but make it significantly less sticky.
Keep your oils in the stove mise in squeeze bottles, or glass with speed-pour tops. I was taught corn and extra virgin olive in a restaurant kitchen, and that's what I still do at home decades later.
I'm from a different time, and would have worked out who should have covered for whom and exactly what that meant either over beer or in the parking lot after work. His choice. Presumably those methods aren't available for you, the second one shouldn't be, and you're more rational than I was (doesn't take much). Next time your "friend" asks you to cover for him, tell him sorry in the nicest possible way, and that you have to wash your hair. Too bad.