...and recast it again and again using Pearls of Psycarnum power.
A level 1 PoSP is only 1,500 gp. (they cost 1.5 times as much as PoP) So with Metamagic school focus, you can toss out a quickened, fell drain Magic Missile very encounter, and still have two uses of the feat left over.
RAW plus your previous arguement say this doesn't work. Because if Midnight Metamagic only functions once per day in one way, it only functions once per day in another. Either both tricks work, or neither does.
The essentia does nothing when invested directly into the spell, unless it's a normal essentia receptacle. Because, by your interpretation, you can only activate Midnight Metamagic once to use the essentia in the spell, this is true.
Go read the text for Pearls of Incarnum Power. (side bar to Soulcaster)
Did before I started this arguement. The "as though it hadn't been cast" clause is meaningless; if you can only use Midnight Metamagic once per day, you can only use midnight metamagic once per day. The essentia being reinvested doesn't do anything because you can ONLY USE MIDNIGHT METAMAGIC ONCE PER DAY, if you are indeed correct.
And again let me point out that that would allow you to quicken every spell you have for free.
Irrelevant unless you have the action economy to abuse it. It doubles your effectiveness by halving your stamina. It's actually a pretty fair trade, in some ways- it makes the wizard equally useful on days with one insane encounter as she is on a day with four average.
Uhm, wizard past level 5 or so have more than enough spells. Double casting is a force multiplier, it's effect is notably more than double the spell slot cost. Because many spells synergize. The whole is more than the sum of its parts and all that.
Okay, level 5 wizard. Let's see.
Spell slots
4 0th, 3 1st, 2 2nd, 1 3rd.
Because you're locked into being an Azurin to pull this off, you're looking at 20-21 Int at best
18 natural
+1 at level 4
+2 from a headband of intellect.
This means you have 4 0th, 5 1st, 3 2nd, 2 3rd. If you're a specialist, add one to all that.
Consider the standard 4 fights/day.
You can only use Your 3rd level "big guns" every other fight. So you can only haste the party twice a day, or haste once and slow the enemies later.
You only get three wondrous glitterdusts/webs. If you're efficient and can pull enemies into webs, you can maybe use them every fight.
1st level spells are likely to be grease, maybe enlarge person, maybe magic missile, depending. These are mostly gravy and basically exist to keep you from having to say "I shoot him with my crossbow. And miss."
0th level spells are mostly convenience matters and RP stuff; most will prepare Detect Magic or Prestidigitation, MAYBE Caltrops if they're industrious and combat focused. Even still, these will at best give you effects that are produced by mundane items in most cases. You don't even have access to Create Water for water devotion cheese.
So, in general, let's consider how the Psycarnum infusion trick affects a character like this.
At 5th level, you are barely going to have the trick up and running. You will likely have midnight metamagic and Improved Essentia Capacity. If you are really optimized, and you have taken two flaws, you can have Wild Talent for a single PP and Psycarnum infusion, and ONE metamagic feat. So all in all, you'll have the trick working and two metamagic feats. At this level, gaining psionic focus is something of a hassle; you have 8 ranks in Concentration, plus maybe a 2-4 point bonus from high constitution. At most, 12. If you can get a masterwork tool, sure, sure. So at best you're looking at +14, which generally means you will often succeed but not always. Meditating as a FULL ROUND ACTION in combat keeps you from doing this while casting- so you are losing actions. So, you are looking at once or twice an encounter getting +2 metamagic free. So, depending on your feat choices, you can Fell Drain, Empower, or Split ray at best. If your choices are more utilitarian, you are looking at more Extending and Sculpting two spells per encounter for free at this level.
So this is doing wonders for your out of combat buffing, but that's about it. I don't see any real doubling of power.
If you wanna extrapolate until about 14th level, that's where you're looking at quickening a spell each round. Which, true, does double your power, but combat is much deadlier at that point. In a lot of ways, you're looking at a free true strike for most rays, etc. Maybe lay down two control effects at once to do some great BC. In fact, the trick only becomes useful in the late game where wizards somewhat taper off- about from the time you get 6th level spells on to just before you're looking at 9th, your power is still great and considerable, but paling in comparison to divine casters.
This trick is certainly great and it does improve the power of Wizards, but not by much. I would honestly compare it to and put it on equal footing as DMM for clerics; the difference is that one can be used more often and thus is more suited to control type actions as Arcane casters do. Considering that you're investing basically your entire career worth of feats to make it REALLY work (need IEC, Midnight Meta, Wild Talent, Psychic Meditation, Psycarnum Infusion, and that's not even counting the Metamagic Feats THEMSELVES which you have to take), the outcome feat for feat is probably WEAKER than taking an equivalent DMM feat for feat.
Just my two CP.