I changed $7B728's value from E1 (raise Strength, Agility, and Vitality 1 point) to E6 (previously unknown) for Dark Knight Cecil's 11th level, and when I ran a new game on the ROM/had DKC level up, it raised the indicated values by 6 points instead of the previous 1. So adding 02 and 04 together gives +6.
Using E5 instead gives a +5 modification. It seems only having 01, 02, and 04 all at the same time produces the -1.
