The main problem with a structure that is "too" stiff is that instead of the energy of the collision being absorbed by the crush zone it is passed on to the occupants. This means there is more energy for the secondary collision - you and the steering wheel or shoulder belts, etc... To this end SN65 hasn't extended anythinig past the shock tower. Reem made his strut so that it will bend in a frontal collision. My strut ends just forward of the front suspension. A strut that reaches all the way to the front of the frame would be stronger but it also eliminates the "crush zone" although I don't think it was engineered as such in 1964. The idea is to survive the collison, not save the car.