Dave Dtroll mentioned along the same lines on Monday and TS was there too, it makes sense as most balls with upwards trajectory (i.e. those which hits a wheel, bike, goal post) might clear the 6m net while having the upper 2 or 3m going inwards at a 45 degrees angle will only very likely eliminate this but at the same time use the same amount of material.
Dave Dtroll mentioned along the same lines on Monday and TS was there too, it makes sense as most balls with upwards trajectory (i.e. those which hits a wheel, bike, goal post) might clear the 6m net while having the upper 2 or 3m going inwards at a 45 degrees angle will only very likely eliminate this but at the same time use the same amount of material.