If difficulty drops to the point where it's profitable again, they turn the rig on. If, as a result, difficulty rises to the point of unprofitability again, th

If difficulty drops to the point where it's profitable again, they turn the rig on. If, as a result, difficulty rises to the point of unprofitability again, they turn them off again. This is basically equilibrium. It's not theoretical, it's what actually happened lately. Difficulty dropped along with price, now it's rising again along with price - but it's still below historical highs.