I wasn't there with calipers so i have no idea if it was an ATC, a Reverso or what. I have found that a normal Reverso is pretty slippery on skinny ropes. That's one reason I switched to the ATC Guide.
I does look like a quality line
But I still think that it sounds more like a III than a IV. 1000' is only like 330m. Say you did it with a 50m rope and it ended up being 9 pitches instead, I still think it would be a Grade III (sure, in the higher end of III) at that length and degree of sustainedness from the individual pitch ratings. But it sounds like it would be a good Alpine D+ for sure.
There was a similar discussion about the NCCS grades a couple of years ago that I have been to lazy to bump up instead of continuing the discussion here.
YDS = Class 3, 4, 5 etc. technicxal difficulty rating
NCCS (oops) = Grade I, II, III, IV, V etc. tme and overall rating.
Grade IV = a long all day climb possibly requiring a bivy on the first ascent.
3/16??? That's dental floss you cheapskate!
And I bet it isn't even stainless.
People placing junk like that keep the ASCA in business fixing their fuckups with decent anchors.
They leave them in Hotels so that when you are stuck with no reading material in some mediocre hotel, you will read the Word of God while sitting on the crapper. It has nothing to do with physical treatment of the book and everything to do with marketing.