When I do flourish in a blue-line mount, i can only do 3 when my reflexes kick in and stop at 3. Any help to break that habit?
You can try doing them one at a time for a while. Then, once that is comfortable, try two at a time for a bit. That might help get you used to stopping consciously on command rather than stopping after three out of habit.
Another thing you could try is get used to doing them in groups of two. Then try doing longer flourishes while counting off 1, 2, 1, 2. That way when you get to the third, you will hopefully be in the mindset that you are in the middle of a two-count and be able to keep going past three.
Also, you can try lengthening your string by a couple of inches. The longer your string, the slow it spins so you just keep going.