Yes, my mom is off coumadin for now, but her case is an exception. Her blood count kept getting low - she's got a "slow leak" somewhere internally, that she was needing transfusions when she was on the coumadin, but stopped being a problem when she came off. Unfortunately, she is still a risk for clotting problems (artificial vein in right leg and past history of stroke). But for the time being she's doing okay with her INR. Her most pressing problems now are keeping her glucose levels in balance and controlling her PD symptoms.
I would say, stick with tweaking her dose and watching her diet as best you can - but it's difficult if they "cheat" when no one's looking. (Mom used to order in pizza, but the boxes were a dead giveaway! LOL!)
Best of luck to you.