The reason Big Green went to the open-on-safe mode of bolt operation is that the chamber can be unloaded while not having the bolt in fire mode. Safety first, foremost, and always.
Older rifles (especially those that have had the trigger adjustment screws mucked with) have been known to fire when the safety is moved to the off position after the trigger has been pulled with the safety on. This is true with all the 700 series; 721,722, 725, 700. The earlier 7 series have a 2 screw adjustment system, and the 700s have a 3 screw system. I've owned dozens of Remmys and never had an AD when taking the safety off, but there is always a first time for everything. See the safety sentence above.