With the little mechanical engineering training I have, I would say the reduction in strength is VERY small, because the cross-sectional area of the material has only been reduced a small amount by grindinding to an edge. Furthermore, I don't think any serious stress concentrations are introduced. I'm a lover of ESEE knives and have several... I'm fascinated by the double edge, but I've elected not to purchase, because such a blade compromises the utility of the knife, and ESEE knives are NOT fighting knives, which is the only reason I can imagine having the double edge.