Strange binding behavior when using binding on array's element

var element = testObject.myArray[0]
element.boolFlag = true

// main.cpp
#include <QGuiApplication>
#include <QQuickWindow>
#include <QQmlApplicationEngine>
#include <QQmlContext>

class Test : public QObject
{

    Q_OBJECT
        Q_PROPERTY(QString emptyString READ getEmptyString NOTIFY valueChanged)
        QString getEmptyString(){ return ""; }

public:
    Test(QObject* parent = 0) : QObject(parent) {}

    Q_INVOKABLE void triggerNotify()
    {
        valueChanged();
    }

signals:
    void valueChanged();
};

int main(int argc, char *argv[])
{
    QGuiApplication app(argc, argv);
    
    QQmlApplicationEngine engine;
    Test* test = new Test(&engine);
    engine.rootContext()->setContextProperty("__test__", (QObject*)test);
    QObject::connect(&engine, &QQmlApplicationEngine::objectCreated, [](QObject* rootObject) {
        QQuickWindow *appWindow = qobject_cast<QQuickWindow *>(rootObject);
        appWindow->show();
    });

    engine.load(QUrl(QStringLiteral("qrc:/ui/main.qml")));
    return app.exec();
}

// main.qml
import QtQuick 2.4
import QtQuick.Controls 1.3

ApplicationWindow {
    id: container

    width: 640
    height: 480

    property int clicksCounter: 0

    Item {
        id: testObject
        property var myArray : [{
            name : "CustomName" + __test__.emptyString,
            boolFlag : false
        }]
    }

    Rectangle {
        x: 10
        y: 10

        width: 100
        height: 100
        color: "red"

        MouseArea {
            anchors.fill: parent
            onClicked: {
                container.clicksCounter++

                console.log("CLICK #" + container.clicksCounter + "[RED SQUARE] : Set testObject.myArray[0] to TRUE\n")
                testObject.myArray[0].boolFlag = true
                console.log("CLICK #" + container.clicksCounter + "[RED SQUARE] : DONE\n")
            }
        }
    }

    Rectangle {
        x: 120
        y: 10

        width: 100
        height: 100
        color: "blue"

        MouseArea {
            anchors.fill: parent
            onClicked: {
                container.clicksCounter++

                console.log("CLICK #" + container.clicksCounter + "[BLUE SQUARE] : Triggering notify by calling C++ <Test::triggerNotify> method \n")
                console.log("CLICK #" + container.clicksCounter + "[BLUE SQUARE] : [BEFORE] testObject.myArray[0].name: " + testObject.myArray[0].name + ', testObject.myArray[0].boolFlag: ' + testObject.myArray[0].boolFlag)
                __test__.triggerNotify()
                console.log("CLICK #" + container.clicksCounter + "[BLUE SQUARE] : [AFTER] testObject.myArray[0].name: " + testObject.myArray[0].name + ', testObject.myArray[0].boolFlag: ' + testObject.myArray[0].boolFlag)
            }
        }
    }
}