To be honest, I don't think I've ever actually used this as a eyelid primer. I don't think I've put it on my eyes at all. But judging from the reviews, it works admirably as such.
I actually started using this as a spot concealer on a whim when I received a sample several months ago. And it's become my absolute go-to product when I need help covering a blemish. The yellow undertones of the product cancel out any redness, it's easy to blend and, like the name suggests, it does not stray, even after a long day. It certainly puts Benefit's actual spot concealer, Erase Paste, to shame. (Too dark, cakey and with the lifespan on your face of a fruit fly.)
Seriously, though. If you have some of this and a blemish, give it a try. The tiniest dot, light blending and just a bit of powder to set and you will be good to go.