I got some pre-shave oil from Art Of Shaving for Christmas, and I am having a little difficulty understanding how it works, despite the directions and a few other articles I have read.

Why lather after applying oil? Is the oil not a good enough lubricant?

After applying the oil, do you apply water before lathering? If so, does that not undo the effect of the oil by rinsing it away?

I am just not quite seeing how to use it properly and how its usage properly fits in or makes sense.

I had cold water shaving down to an art, and I now am trying to figure out how to integrate in the oil. Sorry if I am missing something obvious.