If memory serves, "Tru Cut" pads mean the grit on the pad is the end result on the ball after sanded. This is why CTD may seem more abrasive. Sanding grits are just another Metric vs Imperial type of deal, where based on the system you use, the numbers mean entirely different things.
I'm aware of CAMI which is what we use in the US, FEPA is the European standard, and I believe Japan has their own system as well. A 600 CAMI is a 1200 FEMA, and Japan measures it by the actual micron of the abrasive.
Long story short, as with everything, the world can't agree on a single system, so what all of us think is "1000" could actually be 3 different results based on which system or standard of product we buy. Abralon, Saair, Tru Cut, raw sand paper, scotch brites... You get the idea.
CTDs angle is that because they've designed them specifically for bowling balls, that the grit number on the pad, is the literal abrasion the bowling ball will have, when measured with rA scanning equipment, after sanding.
Therefore the name "True cut" because if you use their 2k pad, the ball will be scanned and read 2k on machinery.