I'm not super convinced by that paper. Their claim of full agonism is really only due to the temperature data (figure 4), and they don't provide comparisons to thc and the cp47 compound that they refer to in the discussion.
Analgesia and catalepsy seem to not increase dose dependently after 5 mg/kg which could either be explained by a ceiling effect or just maximal inhibition.
Marijuana smoking dramatically alters responses to various environmental stimuli. To study this phenomenon, we assessed how delta-9-tetrahydrocannabinol (THC), a primary psychoactive ingredient of marijuana, affects locomotor and brain (nucleus ...
www.ncbi.nlm.nih.gov
Figure 5 in this paper shows a similar dose response of hypothermia with thc for example.
Best info (which I couldn't find) would be a g protein assay which is a very direct way of demonstrating efficacy.