The requirements set forth in this Article concerning the amount, size, location, and nature of parks, public open space, and recreational amenities to be provided in connection with subdivisions and developments are established by City Council as standards that presumptively will result in the provision of that amount of recreational amenities an/or open space that is consistent with officially adopted Community Development Plans. Notwithstanding any provision of these regulations to the contrary, the Planning Commission may, in cases of an unusual or exceptional nature, the underlying objectives of this Article may be achieved even though the standards are not adhered to with mathematical precision and may allow for adjustments in the park land dedication and fee-in-lieu regulations and requirements as established herein.