All this mystifies and saddens me, it really does. I had a shaky start with Wool Fat, because I tried to bowl lather it, but after someone (Manimal I think) put me straight on that, it's been very easy indeed. It really must be a case of the soap being dependent on the water with so many experienced people experiencing problems.
Leaving that aside, because there's not much to be done about it, the relevant factors seem to be 1) a stiffish brush, preferably badger; 2) don't be mean when loading the brush; 3) face lather, and 4) use it regularly.