Thanks, Joe!
Assuming his DV is high compared to the other related skills which is usually the case, the normal (before cap) gain @27 should be somewhere in the range 0.08 - 0.12 per training, meaning that @ 33% (after cap) it should be ~0.03-0.04. 18 trainings times that is ~0.5 - 0.7 total gain without a pop, so 33% still remains a valid guess, consistent with your case.
But yeah, it gets damn slow at the end...
