Jan, I like your logic a lot, and I think the addition of the pictures was extremely helpful in understanding and appreciating your point.

When running games, I would prefer not to look at a chart and modifiers; keep it quick because the gain of realism might not offset the cost in game-play momentum. When playing solo, I have the luxury to explore greater intricacies, so charts are fine. I use them when playing WoG and really enjoy the effects.

I have played games in which the GM spent much time consulting charts and rolling dice; after a while, I started checking out of the game's story, and each turn became separated from the previous and subsequent turns. Too often, the game never reached the conclusion because only a few, highly-detailed turns were completed.