I've run an encounter with one high level fighter (28th level) against 20 27th level minions and a 28th level elite. It was a slaughter, but only for the minions! Details
here.
Yeah, right, on an open plain against one character who could use his AoE and with minions with basically no effect apart from minor hp damage. Now I wonder how he would have fared in any other circumstance in particular with allies in the way and actually effective minions.
40 on-level minions against 5 PCs would not be any sort of slaughter at paragon or epic tier, and probably not even at upper heroic.
Since someone mentioned E2 (which I've played through) I went and had a look, and quite a few of the minions (those I remembered) have very nasty side effect (in particular the rider on their attacks) that would make such a statement very doubtful.
For the same reason that the PCs' AC is higher at higher levels.
So, training then ? But then why does the 3rd level standard have 46 hit points and the 9th level minions have 1 ? The answer is not because it makes sense in the world, for sure. It's purely a gamist construct.
And then we agree. My point being that if that's what you're looking for, the minions' mechanic is the right one for you. If you look for world-wide consistency, it's not, because it's purely gamist.
to manage action resolution across the tiers of play. You could delete all level bonuses and make no difference to play except that now the Monster Manual would no longer suggest a progression across the tiers of play that reflects the "story" of D&D.
Or you could, you know, use the 5e system without minions that makes a difference of play across the tiers why preserving the consistency of the world without relying on such extremely visible gamist strings.
Way more dangerous to whom?
To a PC of let's say intermediate level.
You are assuming that the numbers correlate to elements in the fiction. They don't. In the fiction, a minion ogre of upper paragon level and a standard ogre of upper heroic level are the same.
Except that technically they are completely different for no other reason than "the system requires it to work". My point is that 5e has solved this without requiring such technical juggling, that's all.
We change the numbers to make the game work smoothly. That's all.
And then, my point is that in this domain 5e has the better mechanic because it does not require a number change to run smoothly.
If you want a game in which, instead, the ogre is almost unmissable by the PCs and almost unable to hit them, go for it! But the outcome will not be very different from using the minion except that everything will take longer.
Not necessarily, and at least the overall world consistency will be maintained, there will not be a purely technical quantum leap, and for the players it will be much more satisfying to see their progression.
If you want a game with no scaling to reflect tiers of play and the "story" of D&D, then play 5e rather than 4e! (Which I gather is what you do.) That doesn't make the fiction of 4e inconsistent. What is inconsistent about a heroic PC finding it a bit of a challenge to defeat an ogre, and a paragon PC finding it easy to do so but not entirely free of danger?
Because they are not the same creature at all. It's pure artificial tailoring to make the system work. So more work for the DM