Does anyone else find lapchang souchong (or blends containing it) seem much higher caffeine?

I'm not complaining, but I find whenever I make a pot of Russian Caravan or pure smoked tea, it is much more stimulating than my normal blends. I don't drink it every day because I'm worried about the carcinogens in the smoke but I enjoy it as a treat. If anyone else has noticed this, what do you think causes it?