That's a interesting observation, cao. I agree, it makes a lot of sense.
I have noticed with mean hives that sometimes less is more with smoke. I also used to smoke a mean hive if I was working the hive next to them, but I've stopped doing that now, because I think all it does is alerts the mean bees to my presence. I've had better luck just leaving them entirely alone if I'm in the apiary working other hives.