Hope I'm not standing close to any of you, when the bolt comes down, and all that hot air comes rushing up from 'the entrance' to your new homes!!
Wedge specific shafts should always be used, it's why and what they were designed for.
What could be any other reasoning????
They have even taken any thinking out of the equation for everyone, simplest irons you could build. No R, No S, No X flexes. Just......wedge!! For your wedges, dammit.