you've already said you aren't going to leave if they don't raise your salary. don't let them know this or else they have absolutely 0 incentive to do so.
Sure they have an incentive. I am saying "charge more for my time, and pay me accordingly." They make more money, I make more money, clients are billed the same. Everyone wins. I am just asking to have them leverage my efficiency.
FWIW I had the compensation discussion with the partners yesterday, and they seemed receptive. They also understood immediately what I was proposing, which was simply a longer winded version of the immediately preceding paragraph.