Yeah a deviation of 6 factors over 1T is a lot. Sieving 1T is going to take me into the depths of winter so I hope to find as many factors as possible. Alternately, PRP is projected to give me only 1 or 2 proofs (30:1 speed ratio?) so I think I'm doing the right thing.

Unfortunately, one of the things I'm finding about this project is that nailing anything to within a 30:1 performance ratio is a difficult bit of math. A lot of project variables skew to a factor of 2-4 meaning that overall project performance is a grey area under a factor of 20-30. Meanwhile, sieving is considered a 30:1 improvement over PRP which is the edge of our ability to calculate. Might be why massive sieving has been such a hard sell.