You got the extension for chopping pretty much right, but you also have the loop around your wrist. What you are doing is extending the arc, and thus the power of the chop.

My survival focus is largely on winter, and I rather hypocritically haven't lanyarded a lot of my gear yet. In deep snow, if you drop it, there are times where all you can do is mark the location and wait until spring. But a high visability lanyard (yeah for orange paracord) makes it easier to spot, becuase you get a tail. And lanyards can help secure things to you- use a cheapie key ring biner, clip it to your belt (not a belt loop, they are too weak) and snap your knife and light to it, against the off chance of the sheath/pouch opening. Although I like a dual fastner sheath whenever possible for the little stuff (velcro + fastex, or 'cro or snap with kydex, preferably), as it gives you a similiar degree of security.

The big thing with lanyards, be they for the belt or around the body/neck, is a break away. Loosing your knife is bad. Getting stuck on something and dragged or throttled or literally left hanging with no way to get down is worse.