Why would you use exactly the same technique for every situation? o_O I don't understand! XD
eta should probably mention I was referring to
That's the theory anyway, and for many shooters this is exactly what they do. They see the logic in the centre-pad position and without any questions, or further testing, away they go to shoot.
specifically XD
Well, clearly I wouldn't, but many do. It's done mainly through inexperience and ignorance. Many just don't know that there's another way. Some stumble into it organically and others are taught, yet more never change their trigger position at all. They can still shoot, some really well, but they'll never know if they could have shot better with a different trigger position.