The danger of MDMA + MAO-I

[metalupyour455]

So swim read into the exact process that occurs in the brain with MDMA in this 23 slide slideshow: http://www.dancesafe.org/slideshow/

So swim gets that MAO Inhibitors stop the MAO's from destroying those poor little monoamine neurotransmitters like dopamine and serotonin, and that the hydrogen peroxide created from metabolizing serotonin is neurotoxic (because it oxidizes the neurons, which is bad for them) to the serotonin receptor neuron, along with the dopamine that can accidentally be attracted as well. But anyways, to swim's actual question here, why does the MAO-I prove to be so deadly? Swim sees that they would stop that MAO's from metabolizing all the serotonin, so wouldnt that make one just roll harder? Or does it just go to far?