I think I am picking up what you're putting down. Not necessarily 'Commandos' and 'Insurgents' per se; but, more about the depth and manner they were deployed and unconventional operations they conducted which resulted in the large allocation of resources to deal with them....right? Raids in Depth? The ALCAN was Army Engineers as was the Ledo Road (Brit & US) both projects were a huge reallocation of resources that great improved the Allied logistical infastructure; I just don't know what we want to call it. The other side of the coin would be the "Sea Bees" who either created or repaired facilities accross the Pacific using many innovative techniques and materials: Marsden Matting, Quonset Huts, Mobile Mills and Batch plants. Both the ALCAN and Sea Bees are examples of things not necessarily associated with 'Combat Engineers' of either side. These guys actually created the infastructure for not only combat operations; but, also allowed the forward projection of Logistics. I don't think Germany created an all weather road from Berlin To Stalingrad. Maybe Expeditionary Engineer Units? I don't think either one of those assesments is accurate. I have yet to 'shoot down' anything because it didn't fit my opinion; I may ask you to explain why it's a game changer and support your argument or I may ask if it was the device or method of employment that was responsible for the change. Everyone can come up with a laundry list of shiny objects, the hook is how did they affect anything and was the result worth the effort.