So in an argument we get to the point that the WTS has problems. So what, says her, if you got a meter (or yardstick if you prefer) and one centimeter is missing, are you going to throw it all away? The same, if from the truth are missing only some pieces, is it not the truth? So I reminded her favorite demonstration used to point out why other churches are wrong: you have a glass of water that has one drop of poison. Would you still drink it saying that it's mostly water anyway?
Sometimes it's fun to be an UBM