Unfortunately, because they are not repeated (or the learnings are extrapolated off of a single campaign), there is little accumulation of knowledge or confidence in these results.
It absolutely is, however, the 90-year accumulation of shared knowledge that the US Navy has amassed since 1922 when the first plane was launched from the deck of the USS Langley CV-1.
Mr Gove argued that it was poorer families that had the most to gain as "the accumulation of cultural capital - the acquisition of knowledge - is the key to social mobility".