Deviation between datasheet ESL and actual measurements
The actual inductance of a ceramic capacitor varies a bit across frequency (due to internal molecular alignment I understand).

The typical ESL you show from Murata looks awfully optimistic for an 0805 device; I just went to TDK (where these is a really nice selector and graph generator) and selected a 100nF 0805 part to get the graph of (in particular) Z.

By finding the self resonance (at about 15.8MHz) I calculate that the ESL is just about exactly 1nH at that frequency and will not vary very much (perhaps 10% or so).

In my experience using a lot of different parts, the typical ESL (at any decent frequency of interest) is:

0402: about 680pH

0603: about 850pH

0805: about 1nH

1206: about 1.2nH

1210: about 1nH

The reverse geometry parts have lower ESL due to a shorter path through the device.

Note that the values above are approximate and will vary under environmental conditions and even capacitor ageing; an accurate model simply does not exist (and also depends on the specific manufacturer for materials and process).

It is also of interest to note that the tests done by AVX were well above self-resonance and the lowest frequency shown on the graphs are 1MHz.

For track inductance, my experience is that a 4 thou (100 micron) track 4 thou above a plane is about 5nH / inch.