This is the thin finger and tips crack in between Rock Lobster and Polygrip. It's often toproped and my understanding is that it's only seen a couple leads.
Location
Thin crack in between Rock Lobster and Polygrip. Shares anchor with Polygrip, but is commonly toproped from anchors on Rock Lobster.
Protection
Thin stuff up to 1.5 Friend, heavy in tips and finger sizes.
I agree that this route is most often toproped. I have lead it and know of multiple others who have as well. Pro is safe and plentiful. It actually takes stoppers in multiple places. My guess is that it has seem more than the "couple" leads the original poster claims it's seem.