John was taken aback by her anger, this was not a pretence for a better bargaining position, she was truly offended by the offer. 

John laid his chop sticks down, bowed slightly and very calmly said "please, accept my deepest apologies! I meant you no offense, truly! I'm a custom to everyone haggling for a better cut, if I offer 50 percent then they want 70 or 75. I believe a 50/50 split is fair, you are undoubtedly the superior swordsman but I'll  more than carry my weight of the fighting and I've already done all the work of tracking down and setting up the job. If this is unacceptable I understand but please know I meant no offense!"