One thing that comes up in a lot of combat rules analysis (especially for GURPS) is what I think of as "the myth of the featureless plain."
You probably know what I'm thinking.
No prior damage or exhaustion.
No time limit.
Unlimited room to retreat.
No lighting penalties.
No bad footing.
No level/height differences.
No terrain, really.
Just a big, wide open hex mat on white paper that extends forever in all directions.
It's on this battlefield many hypothetical situations fight it out. The Reach 2 guy who you can never close with. The close combat fighter who can never grapple anyone. The shield guy you can't flank. The Counterattack or Riposte or Arm Lock specialist who auto-kills you if you attack and has a single super move that you can't counter. The DX monster you can't touch or the ST monster you can't hold on to. Dodge Man who avoids all attacks with ease. Defensive Grip dude who takes his +1 because the penalty for a flank defense never comes up, because you can't get to his flank.
You know, your completely atypical battlefield.
I call it a myth because you have to really work to make that happen in a game.
In most campaigns, this doesn't happen. It's rare to get a truly unmodified skill roll in circumstances where nothing outside of you and your opponent can affect the next few seconds. It's possible, but it's rare.
Even in a duel, you won't get this. No walls? No edge of the dueling arena? No cheating? No outside interference?
It doesn't happen even in structured environments. Grappling matches re-set you to the middle if you go off the edge of the mat. Fighters get separated and re-started if they go too far or do too little. This kind of thing happens - cage fights have cages, so you can circle but a clever fighter can box you in. Tournaments have fighting areas. Duels have an agreed upon ground and features in an around that.
Never mind actual melees. You know, with multiple combatants and unfair setups and situations where Arm Lock dude really doesn't want to grapple you because he needs his Parry against the next guy. Or where Counterattack dude leaves you alone because he's got problems elsewhere. Or back shots, or bad footing from blood and sand and dead bodies, and random missiles that thump you from a flank because your friend made his Dodge and the arrow kept on going into you instead.
This is why I often gripe about the one-on-one featureless plain basis of analysis. It's not a bad way to start your analysis of a rule, but it's not the end of it. A lot of the uber-tactics of the featureless plain are just foolishly suicidal in a melee, or might be merely risky. What might work great one-on-one on a featureless plain isn't as effective in bad lighting, on bad footing, when you're tired and wounded from the fight just before. High-cost tactics (Extra Effort in Combat, say) might not cost anything in a short fight but cost greatly if you don't get to rest before more folks come. There are costs and benefits that might not be apparent in just this circumstance.
Not every fight takes place in Nogard. Few, in fact, do. And if your game features more featureless plains than dark, dingy places with uneven footing and mismatched fights, you might want to consider looking at B402 for inspiration, just for a start. In my own games, a fight without some basic penalties is a pretty rare thing, and the more cramped spaces, terrain issues, and "don't step there!" hexes I can manage, the better. Battles are rarely fought in ideal circumstances for either combatant. So mix it up - and see how things work when everything is less than ideal.