NPPF and Open Space issues - Public forum - Planning Advisory Service (PAS)

I wonder if anyone can help me with the NPPF and “open space” issues. Please bare with me as there are a lot of fairly pedantic points and questions. Most of the points relate to how vaguely worded the NPPF is. Within the urban area in our Local Authority, most of our open space is designated as Urban Greenspace – this includes publicly owned and/or accessible sites and also private sites. We are currently experiencing pressure for development, particularly on some privately owned Urban Greenspaces. However, as with many things, the NPPF and its vague wording is not helping. NPPF paragraphs 73 and 74 deal with the need to provide and protect “open space, sports and recreational buildings and land, including playing fields” and also under what circumstances that they may be built on. The NPPF goes on to define what they mean by an open space. This definition is as follows: Open space: "All open space of public value, including not just land, but also areas of water (such as rivers, canals, lakes and reservoirs) which offer important opportunities for sport and recreation and can act as a visual amenity." I find that this definition leaves more questions than answers. Does the “…important opportunities for sport and recreation and can act as a visual amenity” part of the definition apply only to the defined areas of water? The wording and punctuation of the sentence would suggest so but logic suggests otherwise and should also apply to land based open spaces i.e. to ‘all open space’. The definition says “…which offer important opportunities for sport and recreation and can act as a visual amenity. The word "and" concerns me because it implies that visual amenity alone isn’t enough and is only important where there are important opportunities for sport and recreation. From my experience some green spaces are important "because" of their visual amenity in providing relief from continuous built development. The term "can act as a visual amenity" is also unhelpful as any open space could potentially do so. The term "public value" is also unclear in its meaning. Does it mean that it has a value for the public in terms of the reasons specified in the definition (sport, recreation etc) or does it mean valued by the public? For example, if an application for planning permission to develop on an open space with no public access and privately owned, surrounded by 5 metre high walls and the local residents submit a petition saying that they value the site as an open space does this mean that it has public value? One individual has said that the NPPF paragraph 74 does not apply to their site because it is not publicly accessible and so it is not of public value and therefore does not fall under the NPPF definition of Open Space. My questions are whether anyone can help here. In particular, has anyone had a post-NPPF appeal decision where an Inspector has clarified any of the above? If anyone has had a legal opinion it would also be interesting. I appreciate that there are a lot of questions in here and my comments may seem pedantic but the problem is that we are being challenged on these things and there are no easy answers.