Interesting. I've never heard of doing this, except with a thread conditioner. I don't even remember what that was called, it was clear and came in a bottle with a squeeze tip on it. Used for metallic threads, mainly.
It's hard to believe that the "lubricated" thread doesn't leave any oil - but I'd love to have less lint. I actually have 2 spools of Mettler thread that still have a wrapper on them, but was going to give away bc I find it linty. Now I feel like I need to give this a try!