That's not really about the numbers. Also, if it is, then why use altering monster stats to undermine those numbers?
Which would be fine. Except why undermine it by altering monster stats then? How 4e instructs to be played is that once monster would no longer be threat to you due the number discrepancy, you replace it a lower they (from solo to elite to normal to minion) version, which represent similar monster, but can hit and damage you. It just feels confused.
I don't understand what you mean by "undermining", and I don't know what it is confused. I never found it confusing.
D&D has, since the alternative combat system in Book1 Men & Magic, used a combination - if you prefer, interaction - of
to hit chance and
damage spread to represent threat-per-attack-action; and has used the combination of
AC and
hit points to represent durability. Durability, in turn, determines the number of rounds and hence - via the creatures attacks-per-round - the number of attack actions obtained before defeat.
Restatting a standard creature as a minion changes the combination of AC and hit points, so its durability is re-expressed in a way that better interacts with the general expectations of the combat rules. (Such as typical % chance to hit.) The restatting also changes the combination of to hit chance and damage spread, also in a way that better interacts with the general expectations of the combat rules, including (in this case) not only average damage done via % chance to hit, but also expectations around condition infliction. A minion also generates less GM-side notekeeping, because its durability manifests as
a reasonable mechanical chance to be missed rather than
a reasonable mechanical chance to not be one-shotted via the damage roll.
The same is true when using elites: when I presented a powerful NPC wizard as a paragon tier elite (I think it was - maybe even solo, but my memory has faded), this makes for more interesting play. Instead of getting a single roll to hit for lots of damage, there are two rolls for level-appropriate damage (as befits an elite's action economy). Instead of just higher defences and hence little chance of being hit and hence little chance of being subjected to conditions, the NPC has a typical chance of being hit, but interesting reaction-type abilities to respond to hits and the like. This makes, in my view, for better game play.
Yes, one could use escalating numbers to show that higher level creatures completely outclass lower level ones, but 4e doesn't do that as enemies are always level appropriate and their stats get changed so that things are hittable.
As
@Charlaquin points out, this is carried by the interplay of mechanics and fiction. Changing the stats of (say) a Minotaur from 11th level standard to 19th level minion reveals that the PCs have come to outclass it it. An upper paragon tier PC will find that 19th level minion relatively straightforward to dispatch, perhaps after taking a sharp blow from it. The reason for the re-statting - as per what I've said above - is to support the game play.
But the fiction is not tied to the numbers, as the numbers get changed arbitrarily anyway. There is no fixed giant stats, as it could be solo giant with low AC and attack bonus or a minion giant with high AC and attack bonus. You don't have a static benchmark to compare the numbers to.
The fiction is indirectly tied to the numbers: it is tied to
tier and
level, mediated through further classifications as standard, minion, elite, etc.
If, somewhere in paragon tier, the PCs encounter a creature who is a
standard monster, then when the PCs, at epic tier, encounter a creature who is - in the fiction - much the same, the players would expect the creature to be statted differently. I've posted examples already - mid-paragon PCs fighting Hobgoblin phalanxes (ie creatures that in mechanical terms are swarms, and that, in the fiction, represent twenty to fifty Hobgoblins).
The minion/standard contrast can also be used for a more "meta" narrative purpose, and I've done this at all tiers in 4e: if many creatures in a group of NPCs are statted as minions, then the standards can be called out as those who are tough or lucky (action cinema style); while the elites are the true "bosses".
A 4e campaign where you fight nothing but goblins from 1st level to 30th has you graduating from fighting the nameless hordes that dwell beneath the Sawtooth Mountains, to fighting Gargaroth the Elf-Slayer and his personal entourage of peerless goblin warriors, to fighting the unholy legions of Maglubiet, hand-chosen from among history’s greatest goblin warlords to ascend to her side. A 5e campaign where you fight nothing but goblins from 1st to 20th level has you graduating from fighting four or five goblins, to fighting six or seven goblins, to fighting ten to twelve goblins, to fighting twenty to thirty goblins. Neither story is strictly better or worse, but they are very different.
I 100% agree that they are different, and I personally have a strong preference for one over the other. You capture here precisely what I mean when I say the 4e approach supports a different sort of fiction from the "bounded accuracy" approach.
I've never played or even seen 4E in play, but it seems to me to suffer the same problem most D&D games have IMO:
You go through a region at low levels, finding goblins, wolves, etc. Later on you return to the same region only now to find it plagued by giants and lycanthropes and such. Still later on, the region is overrun by dragons, beholders, and liches.
The world should not "change" simply because the PCs become higher levels.
So, as I understand it, at higher levels in 4E you can fight the same monsters you did at lower levels, but now they are simply "more powerful" versions of the same things? You go from orc, to orc warrior, to orc marauder, to orc war chief, or orc warlord and orc elite rampagers...
All of those different sorts of orcs should already exist, and their rarity determined by things other than the PCs' levels.
You've had replies, and I'll add mine: the DMG and PHB give clear advice on this. It is under the heading Tiers of Play. A game in which the GM ignores that advice, and does not build the fiction in a way that correlates with the growing might of the PCs, may be silly. But that does not seem to be a problem with 4e; it seems to be a problem with the GM not following the advice.
I'll elaborate on an actual play example I've already mentioned in this thread: at low-to-mid Heroic tier, the PCs fight small Goblin and Hobgoblin raiding parties, saving a homestead and rescuing some villagers. At upper Heroic tier, they enter a fortress where they defeat its guards and inhabitants handily. At the beginning of Paragon tier, they are able to defeat a force of Hobgoblins and some magic-using hangers-on, including a behemoth (a triceratops, from memory), who have set fire to a village and are on their way to assault the town. The Tiefling PC is able to break through the wall of a burning building to rescue people trapped inside. At mid-Paragon tier, the PCs infiltrate and assault the Hobgoblin army encampment, defeating Hobgoblin phalanxes, although one PC is killed by an angel sent by Bane to support the Hobgoblins.
This is what I mean by the fiction revealing the PCs' progress. And it has nothing to do with the world "changing" because the PCs are higher level. What the PCs can do changes because they are higher level. After the events described in the previous paragraph, the PCs entered the Underdark, where eventually they killed Torog; and undertook travels through the Abyss, which they eventually sealed after killing Lolth and Orcus.
I know I'm touching the third rail here, but you know what that feels like to me? MMORPG design. You go from killing boars in the Level 10 zone to killing dire boars in the Level 20 zone to killing dire hellboars in the Level 30 zone. Which I mean, a lot of people are obviously fine with that gameplay style. But not everyone is, or at least many of them are less happy to find it cropping up in their D&D.
Questions of good or bad aside, D&D 4e was a very different game in so many ways.
Your use of the second person ("you go from") seems a bit gratuitous to me. I mean, that's maybe how you played 4e D&D - I don't know, I wasn't there. But as per what I wrote just above, it is not what the rulebooks advise, and is nothing like my own experience (which closely followed that advice).