One issue regarding lanyards:
With a monkeys fist or any lanyard that ends with a large knot at the terminal end, you do stand the chance of having the knife pulled from a pocket or open sheath by something that catches the lanyard. I use a coil type knot to minimize the odds of a lanyard becoming entangled or hung up in brush or other objects.
In general, I have found that a lanyard is not functional for EDC.