Not so benign is the prospect of falling rocks in the Rotten Fork blasting project. That one has been, I trust, abandoned. Maybe there are people who know more about that sort of thing. Let them try. Another danger of hammering is injury due to poor aim.
Some people prefer to get it over with and hit their thumb right away.
I usually wait until it happens naturally. Part of the macho of hammering is the mashed hand you get in the line of duty. Wearing gloves is a good idea. This can prevent the lacerations obtained from scraping the wall as you hammer. It is also possible to hit yourself in the head when the hammer bounces back from the rock.