The suggested route can easily be shortened in several ways.
One option to avoid the circular portion of the route is to take the grassy path straight ahead at (3) rather than turning left. Point (4) is then 650 m away instead of 2.45 km, saving 1.8 km.
A second, much more radical option is to turn right at (3) and continue more or less straight on to point (6). Here, the shortcut is 4.5 km.
The third option is to continue straight on at (8) and follow the long-distance hiking trail (GR® 15, red and white markings) to point (11), which offers a shortcut of 3.1 km.
A little bonus instead of the minor and major shortcuts suggested above:
At (9), a short walk of a few hundred metres there and back along the road takes you to the observation tower overlooking the Fagne de Pouhon and the Sources de l'Aisne.
(10) On a clear day, there is a beautiful view in the distance of the hills beyond the eastern Ourthe, Houffalize and the Bastogne–Sainte-Ode axis