I am not sure if it's even possible to accurately measure 1st and 2nd moment changes in load to a fine extent that you can quickly (edit) detect bursts and distinguish them from noise. Also, the analogy about the link seems isn't quite right; you shouldn't be pushing the link to its maximum capacity.

This is because traffic is rarely "smooth." Even if you say the link is operating at 90% utilisation, you usually refer to the average. Pushing a system to high load can lead to instabilities and unpredictable performance.