Why would you design a gun which necessitates the pulling of the trigger for anything other than shooting? It makes absolutely no sense to me.
If you sell 1 million guns, guaranteed that statistically 20 or so will take down the gun negligently.
It is a design looking for trouble.
Only someone who knowlingly ignores some of the 4 rules could be in favor of it.
The only ones that will get hurt by their design during this function are those willing to disassemble a weapon while it is still loaded.
It isn't for everyone, and I didn't like it at first. But I have become used to it and happy with it.
Some people are better off without that feature; I could suggest knitting for those but they might hurt themselves with the pointy sticks.
Since the gun I learned to shoot with as a child had a similiar feature, I guess I just don't see it as strange. It is not a Glock only design and applies to different types of firearms and has for decades.
http://www.marlinfirearms.com/pdfs/manuals/MFC_Bolt_Action_RF.pdf