The dose an ordinary person (not a regular abuser) would take.

Coke is not equal (I mean it is arguably zero harm if taken rarely, but pretty addictive and serious harm if taken regularly), MDMA and meth are extremely similar substances chemically (MA=meth) and have similar mechanisms of action. Same harm prevention techniques work great with both. The most important difference is MDMA being harder to abuse than meth is, because a number of reasons. Most of MDMA users take it occasionally for good, most of meth users take it regularly for harm. AFAIK. Obviously there are many exceptions.