<i>Calling thirst will give you infinite movement for the duration of thirst. You could walk all over thera while thirsting and flurry a million times.

When the thirst wears off, all those moves will be gone and if you went into the negative, you are stuck in whatever room you are in when the thirst wears off, and you won't even begin to heal those moves back until the battle fatigue wears off.</i>

So this means that you use mv normally when thirsting, you're just allowed to overexhaust yourself and go to the negatives instead of being too tired to move while thirsting.