Hi Michael !
I think this should rise an error
createPoint(moi.vectorMath.add(obj.getStartPt(), scaleVector(obj.evaluateTangent(obj.domainMin), -1))).commit() - correct state
createPoint(moi.vectorMath.add(obj.getStartPt(), scaleVector(obj.evaluateTangent(obj.domainMin)),-1)).commit() - should rise -> it creates an null point

function scaleVector(v, factor) ... return moi.vectorMath.createPoint(x,y,z)