The telling comment from Mo Vines in the above article is "I think, ultimately, they want to graze it."
When the slopes are cleared of scrub and reseeded, the grass will be grazed by sheep. Dogs and sheep do not go together well, and the dog walkers will not be happy with this disruption to their dog-walking activity. There have been dog attacks on the flock in the field next to Old Sarum, and a notice up there at the moment reminds dog-owners that their dogs must be kept on a short leash when in the same field as the sheep.
There was a similar reaction from dog-walkers at St Catherines Hill hillfort (near Winchester) when a flock of sheep was introduced to graze the grassland on the nature reserve .
Something is not right. This message is just to keep things from messing up down the road