New hives with no stores are generally quite docile, and I started out not even using a veil all the time.
Then one day in early September I opened up the hive barehanded to check on the honey super and got stung three times in the fingers before I could get the inner cover off, and three times in the ears before I managed to get the covers back on.
Use the smoke, it only takes a couple minutes and really does keep them calm. It appears to prevent them from smelling the alarm pheromones and that keeps them from mass attacking you! It is disruptive to normal hive commumications, but then so is taking the hive apart.
Veil and smoker, every time you open a hive, will keep you from some nasty experiences. Cheap insurance, even if you don't actually use the smoker.
The only exception would be hiving a package. I have not used smoke then, usually it's cool here when packages arrive, and often drizzly and the bees don't fly much at all. They only want to be in a nice warm hive all clustered up, so there is no need for smoke.
Peter