Resonant Depolarization at LEP: Simple Explanation?

Question

I'm looking for a simple explanation of how the idea of resonant depolarization can be used to measure the beam energy at the Large Electron-Positron Collider (LEP). I understand that the amount of spin precessions $\nu$ in one turn in the collider circle of the $e^-$ are proportional to the beam energy $E$. But how is $\nu$ measured? Can someone explain it in simple terms? The papers I found are really an overkill and I can't find what the main idea to measure $\nu$ is.