Now you've said that i can see wot u mean, he does look 'bengal' dark but if someone were to have told me he was a pure Amur i'd probably hav believed them i find it can be quite hard to tell a hybrid tiger sometimes, in some cases its obvious like a sumatran/amur cross, but bengal/amurs can be hard to spot if you're not an expert...
Haha, i see wot you mean, i couldn't really tell from this pic (tis a great photo) but i just had a look now on google & found some pics of Sasha in full profile & he does blatently look like a hybrid. His head and front paws look like Amur, but his build and tail suggest bengal or maybe Indo-chinese. Still a stunning animal though i gotta admit