Regarding the usefulness of large folders-
One of my daily carry knives is a Cold Steel Ti-Lite 6, 13" overall length, 6" blade. Even I would not have considered it to be a "practical" knife. But I was wrong. I've only used it twice, but it proved indispensable both times.
1. I was at Walmart to buy a box of cereal. The cereal I wanted was not in stock in it's normal place on the shelf, but looking up I could see there were several boxes of it on the very top of the shelf where they keep the overstock. There was no way I could reach it with my hand, and even if I could jump up that high and reach it the boxes were packed in so close together I wouldn't have been able to grab onto one. There was no one around, so I pulled out my Ti-Lite, opened it, reached up, stuck the tip of the blade into the bottom of the box, and pulled it out so it could fall and I caught it with my other hand. A knife a few inches shorter wouldn't have reached it.
2. I was at a friends barbecue, my bratwurst was ready to come off the grill, but my friend had disappeared with the tongs (the only bbq utensil he had), so I pulled out my Ti-Lite, reached across the grill, skewered my bratwurst, lifted it off the grill saving it from a flame-broiled death, and without having to burn my fingers.
You just never know when a large knife is going to come in handy for something, even a 13" stiletto

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