I wrote: "any weapon that is at least 3/4ths the size of an opponent has a further +1 advantage". I was about to change this to 2/3rds, on the principal that, for a human of an average height of 6 feet, that would be a 4-foot long weapon. But then I thought "it might be worth it to explain why I picked 6 feet as the average human height, instead of looking it up or using a shorter height to suggest a medieval feel, or using metric instead."
6 feet works well with random rolls of 1d6.
If I wanted to randomly determine where a dart struck a human character, I could roll a d6. If I wanted to randomly determin weapon length, I could roll a d6. It's a cheap trick to make things easier. It's the same reasoning as using time units that are 1/6th of various standard units: I can roll a d6 to determine which turn something happens during a one-hour period, for example. It's also similar to using a hexagon as a template for determining random directions:
- 1: North/Forward
- 2: NE/Front Right
- 3: SE/Right Flank
- 4: South/Rear
- 5: SW/Left Flank
- 6: NW/Front Left
I am in favor of anything cheap and easy.