I am torn. So listen to this internal conversation:
ConBon: I think it's important that we understand the conditions and reality of combat in the Middle Ages. We want our games to reflect life, even when there are dragons and baby-wizard-clones.
CWilly: I disagree, an attack in D&D is an abstracted way of simulating the action of swinging a sword. We have precluded the need to understand the swing of the sword by having game designers and dungeon masters assign attributes to weapons.
CB: So? If one of our players wanted to use the pommel of his sword to bludgeon a skeleton I would probably let him do that with no penalty, though for less damage than a sword swing. The players understanding of how a sword was built and used improves their ability to use it in game.
CW: Fair point, but the player that doesn't know that may be at a disadvantage.
CB: Good! That will encourage them to learn about their weapons and skills and really immerse themselves in the setting!
CW: No, I think it introduces a layer of complexity and inaccessibility to the game that detracts from its enjoyment. We should absolutely want to encourage immersion and creativity, but never at the cost of penalizing players with less "Player Skill".
CB: Touché my dear fellow. But I still hold that the DM have at least some idea of the means of combat in the setting/era that the game is taking place in. They don't always have to use/include this deeper knowledge, but the ability to answer the PCs probing questions with logical and thoughtful answers is valuable.
CW: Oh absolutely, but the same could be said about having a coherent idea of how magic works in the world. As long as you have a good idea about how you want it to work you can kind of make it up as you go along. Magic laser tanks don't exist, but if a PC asks if their is a self destruct button in one then the answer will vary on what role you want magic laser tanks to play in your Campaign.
And they walk hand in hand into the sunset still arguing...
Some of this may also help make a setting feel more sparse and "gritty" (though I am hesitant to use the phrase). For example, swords were incredibly expensive to make and not very versatile in their uses. Should a fist level warrior-type just starting out on their adventure be able to even have access to a sword? Or perhaps you can have a sword if your daddy was rich, but you get a wood cutting axe or a sickle or a spear otherwise.
I saw something come out of the D&D 5e Homebrew Tumblr a few months back that had stats for Dark Age weapons like seaxes and such. While I like the commitment to the setting and creating usable tools/analogs for DMs to run games in Dark Age Europe, I don't think that it is important to stat a heavy seaxe any differently than a greatsword. Its the same problem I have with the near-fetish like attention D20Modern pays to different gun stats. I don't really care what model Glock I have, I just wanna shoot stuff.
Now when I think of D&D 5e players I think of a lot of young professionals (~20s and 30s) just trying out D&D for the first time. I assume I have a better grasp of medieval combat than they do. But does that mean that my games are more fun? Or does it even mean that my games are a more accurate simulation of what combat would be like if medieval folks where fighting horrible magical monsters? Are those desirable goals? I dunno. What do you think?