The civlopedia says this ritual reduces the counter by 5.
I have built the ritual quite a few times and never seen that.
I have seen mostly 2 or 3, but also once 4 and once 1.
Yes, I know there are some things that probably affect this:
1. Rounding. I just love that one.
2. An event that would increase the counter the same turn you built the ritual. However, I have not heard that counter 'sound' before the ritual, so I'm not sure about that one.
Maybe it would be just better to change the entry to reflect the 'real' counter and say the Hallowing of the Elohim will reduce the counter 1 - 5 pts.
By the way, in my Epic game, I have been able to build the ritual every 12 turns or so reducing the counter back close to zero. No blight yet and this game will not see the horsemen. I even researched Ashen Veil because none of the AI civs did - they (7 of them left) were all Neutral.