this phrase suggests a static goal based on science available today. In Paragraph I.24 there is mention of a review of the obligations, but the scope of such review is not clearly delineated (quantitative goals!, institutional arrangements!, substances?).
Ongoing research obtains new insights, including on substances ( with a role in athmospheric processes) that may not fit the strict definition of GHG (as those gaseous constituents of the atmosphere, both natural and anthropogenic, that absorb and re-emit infrared radiation (Art. 1.5 of the Convention)).
By allowing for the periodic alignment of the goal to progressing science (and innovation), the strategy can become flexible/adaptive, and climate/atmosphere-related challenges can be addressed within the same agreed institutional infrastructure (rather than to require new agreements with their implied costs and delays). Consider (retrospectively) the actions on CFC's and Ozone.
Likewise, reporting templates will have to be adapted, and emerging substances can be addressed efficiently.
See in this context: http://www.sciencemag.org/cgi/content/summary/326/5953/672 ; http://www.sciencemag.org/cgi/content/abstract/326/5953/716 ; and http://www.sciencemag.org/cgi/content/summary/326/5952/526
