So dear reader(s), time for an update on my Vaseline experiment. I've been using Vaseline on my eyelashes on and off for the last month, and I wish I had a decent camera to document the results. I've tried using my mac web-cam, but you can't see a noticeable difference.
I will describe to you the effects I had, personally, though.
While I don't see any drastic changes in length or thickness, I do seem to have way more individual lashes than I used to. It seem they are growing in layers, giving the illusion of thickness. I didn't experience any breakouts, or irritation or anything of the sort. So if you think you can benefit from experimenting yourself, feel free.
Of course, if you do experience any ill-effects, stop immediately. Just because my skin didn't react, doesn't mean yours won't.