As you can see, I'm no lawyer! But this is from experience (fair enough, of a singular case) where local contractors hung a cable that, when translated vertically to ground level, encroached over our land. I approached the contractor directly (the boss hasn't overseen this specific piece of work) and he saw enough possible red tape to get his guys to shift it about five metres away, citing the reasons I quoted above.
So perhaps 'twas in fact a misunderstanding on both our parts that led to the result I wanted?! But he looked totally uncertain when I could see him initially considering refusing my request.