The section on which the marking is located is actually a nice change from the asphalted cycle path: narrow (unfortunately at the height of the handlebars at the moment😉) and in a few places with a breaking edge, a small wall crossing experience and like on the long rest of the cycle path it always goes up and down. The trail demands constant attention and an MTB is certainly the bike of choice here, but you still don't need sophisticated riding technique. So I don't understand why passage is now generally prohibited here. The bypass is boring.