At a match today, our fourth stage had a table start. I was on the pad, as pat of the RO team. A talented shooter picked up his Shadow 2 CO pistol, which was hammer down, and ND'd a round into the start table. I stopped him, made sure he and everyone was OK, and then asked what happened. It turns out when he was picking up the pistol, his grip was slightly off, and his middle finger on his strong hand went into the trigger guard as opposed to below it. When he closed his hand forming his grip, his middle finger pulled the trigger.
It shows you that while a DA trigger may offer some extra safety in handling, that your normal grip is more than a DA pull.