I think there's a lot of techniques that are overlooked these days. Behind the Neck Press for instance.
Casey Butt has written about it and with the proper technique and flexibility it is a great exercise. I will try to find
Casey's post about it. It totally changed the exercise for me!
Yes, the PBN was the glod standart for Reg. I began training hard with this exercise several years ago, in my first serious and complete cycle. In the beginning the luck of elasticity is not a real problem, but when you have to train near your first plateau level, starting the movement with the BB laying in your traps plus the stress due to the stretching of the delts in this position can be a problem. So it happens to me with 40 kg PBN. So I change to military press, and I gain some extra kg in the lift. Maybe stretching this area could help, with a BB or a piece of wood lowering below the traps to the middle back, like the dislocation of the gymnasts. Maybe the straight arm middle grip BB pullover can help; this last is very demanding for the elasticity of the delts even with few kg.