Tanks can never become balanced until you tone down anti-tank itemization.
The purpose of a tank should be to draw attention and soak up damage/CC. The threat is minor amounts of damage (minor, Darius is not a f*cking tank) and threateningly long durations of CC. Tanks build a combination of resists and health to achieve this purpose, and their natural tankiness and tank steroids/utility allow them to live much longer than any other champion building the same items.
However, itemization towards tanks boils down to doing one of two things: bypassing their resistances and going through their health pools faster. That's all fine and dandy until you consider how much of both is provided for AD:
(For this section, we are going to use a relatively standard tank (with no bonus resists or shields for simplicity, adding 9 armor for runes): 
Level 14, with a build of 
##NOTE: I put the calculations in little quote boxes so that if you're like me and reading math makes you sick, you can just read the non-quote boxes and you don't have to see the numbers.
#Resistance Bypass:
With minimal effort, removes 30% of target's total armor.
(69.5+9+150)= ~229 armor Now, we add the shred: 0.7(228.5)= ~160 armor So, essentially, 229 ⇒ 160
##That is a 69 armor reduction. That is basically the armor from your plus all 9 of your armor runes negated by a 3k gold item.
// Passively grants +45% bonus armor penetration.
>(69.5+9+150)= ~229 armor
EDIT: (Credit to Backup4now for this correction) Let's ignore that armor: (69.5+[.55(9+150))= ~157 armor
So, essentially, **229 ⇒ 157**
##Last Whisper and its upgrades reduce armor by 72. That is a , a , and 2 of your armor yellows ignored completely by a 1300 gold item.
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#Health Burn
 Deals 8% of your current's target HP in physical damage.
 Grants +15% physical damage against our tank
>(1629+1.15(300+500+400))= 3,009 HP
Let's say our attacker is a level 14 Twitch with only BoRK and LDR and he took attack damage reds. So, his full auto damage is:
>1.15((84.6+40+50)+.08(3,009))= ~478 damage per auto attack (More than an IE crit at the ~175 AD he has now)
Normally, the damage reduction is as follows:
>100/(100+229)= ~0.3
~0.3(478)= ****
##Normally, it would take 21 hits to kill this Amumu at this level of damage. 21 auto attacks with only this amount of AD and BoRK (I know it's current health, don't make me calculate this shit for every single auto).
Now let's factor in the armor ignore:
>100/(100+157)= . 39
.39(478)= **~186**
##Now it will take a little more than 16 hits to kill this Amumu. That's 5 hits less.
Now let's say your top laner (it's probably that f*cking Darius) or your ~~jungler~~ Lee Sin has Black Cleaver and works their magic.
(Since armor reduction applies first, we'll calculate accordingly.)
>(69.5+9+150)= ~229 armor
EDIT: (Again, credit to Backup4now) Boom, shred: ([69.5 x .7]+[(9+150) x .7])= ~160 armor
Now we add the armor ignore on Lord Dominik's Regards:
>100/(111.3+88)= ~.50
.50(478)= ~240
##So basically, in the respective order of no penetration ⇒ LDR ⇒LDR+BC we get this neat little flow chart of damage:
##143.4 ⇒ 186 ⇒ 240damage
##So we went from 21 ⇒14 ⇒ 13 hits for Amumu to be killed. By a late game ADC with one core item, no Doran's blade, and an armor item. He doesn't even have crit or any real semblance of AD and he's already able to kill this Amumu just fine.
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This little demonstration of messy calculations was to show you how absurd AD tank shred is. Until we tone this shit down, tanks will always have to deal damage, will always get blown up, and we'll never get anywhere. Oh, and Riot is reducing HP and increasing resistances on tank items now, so... yeah. Yay.
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#Q&A Session
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##1. Hey, ~~Melledoneus,~~ JarvansWAR, what about crit? What would it be then?
Fuck you I'm not doing those calculations. I'd rather take a nap. Q&A session over.
vs. an all AD team with a tank support, build nothing but armor and HP, and still get burned down in less than 3 seconds.
