I agree but have to address the size reference. BAC is the measurement of the percentage of alcohol in your blood, hence size has nothing to do with the degree of intoxication between differently sized people with the same BAC. IOW, a 6' 200 lb man is just as drunk at .12 as a 5'4" 150 lb man would be.
That said, yeah, .12 BAC is not usually Out-of-your-mind-'Honey-did-I-ever-tell-you-about-the-time-I-hit- on-your-kid-sister?' drunk. He has to have some other demon's chasing him for this kind of behavior to be so close to the surface.
He hates Jews.
Gibson could also be manic-depressive, given his well-documented mood swings.