Okay, earlier in this thread you asked me if I custom made every monster in 3e... so now I'm going to ask you a question... did you really only use every monster as a solo for the particular level it's CR matched?
I think your really reaching here to justify your opinions about 4e and 3e. I mean honestly I can use 4 CR 5 monsters to make an encounter with an EL of 9... Thus a 9th level party which is roughly equivalent (taking the disparity between 30 levels vs. 20 levels) to a 4th/5th level party in 4e.
Huh? By my estimates a 9th level party is definitely up into Paragon tier. Even Epic tier doesn't have anything like Wish, Shapechange, Gate, Mordaniken's Disjunction, Implosion, or Storm of Vengenace (although the latter might work) - meaning it caps out before level 17 (spellcaster equivalent). 9th is almost half way between 3rd (roughly equivalent to Level 1) and 16th (roughly equivalent to Level 30). Putting it firmly in the middle.
And yes, I did use multiple monsters in 3e. (Although not as many; minions are easy to run and the explicit assumptions were different, and I trust the CR system about as far as I can throw it - any system like that breaks near the edges).
These selected monsters can have the same type of tactical synergy one finds in 4e...
Tell me when they get (a) Marks and (b) Forced Movement powers.
Personally my primary goal was never creating tactically rich encounters in 3e... it was at best a secondary goal to creating an encounter that made sense and served a purpose in the game as well as the narrative I and my players were playing/creating.
Of course. (At least if you don't want to model your game on Feng Shui - not that there's anything actually wrong with that). But once there
is a combat encounter there, not making it tactically as well as narratively interesting is simply poor craftsmanship.
How about this then (and this is all just me musing on things)... there was tactical depth in properly constructed 3e encounters (where "properly" is used to mean this was one's primary goal), though nowhere near as transparent or as primary to encounters as it became in 4e. So the tools were there... some people just had a harder time using them than others. Perhaps, for these people, 4e feels like it offers a better tacical gameplay experience.
Again, I say 4e has tools like marks, forced movement, and an assumption of and balance for multiple foes. Now you can argue that at a strategic level 3e wins - but tactically it's hard.
And to me the writer that should make *no* difference whatsoever. All my job consists of is to write some interesting encounters tied together with some sort of coherent story. How those encounters get met and dealt with is up to each individual play group that uses my (hypothetical) module.
An encounter that's simply taken down by one spell (Sleep) is not interesting. And what makes things interesting at a tactical level is different between modules. For instance interactive scenery and pushing people down their own pit traps is huge in 4e.
Unless I'm a complete idiot, I'm writing my module for a range of PC levels: 1-3, 5-8, whatever. Given that, I as writer should have at least a vague idea of what a party at that level can do, and keep that in mind while writing. But at that point my assumptions have to end if I'm writing my module for mass consumption, as every group that plays it will play it somewhat differently.
System matters as much as level.
As writer, it's part of my job to at least try and nod to some of those differences in my writing, rather than just say "here's a combat module, if anything happens other than combat you're on your own".
And to nod to those differences
within the combat if you're running different systems with different approaches to combat.
I'd go on but I've a session to run.
Have fun

(My next session is tomorrow).
Well, perhaps not intensely. But even if you're taking an absolutist position, NPC's in encounters don't need to act, and they don't need personal stats (this Skill Challenge will use skill checks vs. a DC of the formula used for monster AC, and require 5 successes before 3 failures. Then, you win the combat! Attack rolls count as skill checks).
Using them that way is one of the big reasons 4e modules clunk.
Most people probably wouldn't find that very satisfying for very long. It might be fine for a combat or two, in a game that didn't revolve around them, but it can't well support your entire session. It's just not varied or interesting enough.
That's assuming you consider the rolling dice to be the highlight of your social resolution mechanic. I don't. I see it merely as a way of keeping score and providing hooks.
You need stats for things that you want to be varied and interesting.
No. I need
information for things I want to be varied and interesting. Stats are simply one form of information. What I need in 4e for social interaction are motivations, habits, nervous tics, level of influence on the world, principles, religion. All the stuff you normally
can't find in stat blocks. Rolling the dice is just a means of keeping score - and the difference between DC17 and DC20 is fundamentally not very interesting.
It's ironic I'm getting this response when in a thread a couple of weeks ago (on RPG.net) I was told that if I rolled dice for social interaction I couldn't be roleplaying.
IMO, that absolutely includes combat. Combat sits at the very head of that table.
Combat is something I want tight mechanics for. That's because every last second matters, it's life or death, and a quarter of an inch can make all the difference. Social can kill you just as dead but it either takes longer or requires more monumental mistakes.
But in D&D, at least, in a game inspired by heroic fantasy, I'd expect Exploration (for dungeons) to sit to his Right,
Can the dungeons. Explore the world!
and Interaction (for NPC's) to sit to his Left, and little Reaction (for sudden things like traps and hiding) is on someone's lap. And you might even have a bit of Simulation (for world building and Gygaxian homage) down at the foot of the table, quiet and unobtrusive, but full of awesome stories if you want to talk to them.
World building helps, certainly.
You want those to be varied and interesting.
And
none of that is on the difference between +5 and +7.
Well, I want those to be varied and interesting.
Which means I need stats for them. And I need actions to happen.
I don't need stats to make most of them varied and interesting. I need fluff - then to match the resolution to the fluff. I don't need my social interactions to snap in the way combat does. (Yes, the dialogue might snap to good effect - but that's not on the dice rolls).