Just a quick noob's guide to Land Doctrines in HOI4.
MOBILE WARFARE
Main users: Germany.
The AI seems most likely to take this doctrine - especially AI Spain.
Giving a starting bonus of a bunch of planning speed, some movement bonuses and Tank breakthrough, the Mobile Warfare doctrine focuses heavily on buffing Motorised and Mechanised Infantry, and, to the same or lesser extent depending on which branch you take, Tanks.
The main bonuses given are to Org - giving Tanks a decent Org - and Breakthrough. This allows for a massed attack on an area followed by a Light Tank/Motorised sweep.
There are two sub-branch splits:
Motorised or Tanks:
Take a large boost to the ORG of Mot/Mech or a bonus to Tank Org & Recovery Rate & the Breakthrough tactic.
Desperate Defence or Modern Blitzkrieg:
5% Recruitable Population or another bonus to Inf/Mot/Mech ORG and Tank Breakthrough. Not really a hard choice. IMO the Desperate Defence should give a sizeable penalty to army capability.
Overall: It suits Tank spam. But it gives no bonuses to Attack or Defence. So it wouldn't suit a stalemate.
SUPERIOR FIREPOWER
Main users: USA, Yugoslavia.
Given that I was a Major Nation in a made-up world with a no-tech start, I would take this doctrine.
Giving a huge starting bonus to Soft Attack, the Superior Firepower doctrine quickly gives a bonus to ORG and DEF of Inf/Mot/Mech - which suits holding the line. The main focus of Superior Firepower is just raw attack.
The main bonuses are changeable based on what branches you take, but the most influential bonus you get get is a whopping 40% bonus to Line Arty Soft Attack.
Edit: This is wrong. It's only 20% or more to basically absolutely everything.
There are two sub-branch splits:
Arty or Support:
Take a bonus to Line Arty recovery rate and Soft Attack, or a large bonus to support company ORG (+20) and Soft Attack (+50% - a huge buff to support Arty that can combine with the later two in Shock and Awe for a 60% Support Arty Soft Attack buff. Line me up for 6-width divisions!)
Airland Battle or Shock 'n' Awe:
Bonuses to the Hard parts of armies and a bit of Air Superiority, or Muh Attack. Both also give a 2% bonus to reinforce rate.
Overall: I like this. I take this as Republican Spain, but like I mentioned earlier I think it really fits a Major country.
GRAND BATTLEPLAN
Main users: UK, France, Japan, Poland.
Turtling. Unfortunately infinite defence doesn't mean infinite staying power, because of the way that stuff works.
Starting off with a whopping bonus to entrenchment (you can reach upwards of 50% really easily) the Grand Battleplan doctrine is, as previously mentioned, basically turtling.
Step 1: Dig in. Give your units a 50% bonus to Attack and Defence.
Step 2: Wait until your planning is maxed out.
Step 3: Play this (I'm not sorry) as your divisions steamroll the enemy with a 50-60% plus planning bonus.
Step 4: Rinse and repeat.
The main focus is, of course, planning. I can remember back to 1.4 when the second tech gave a 30% buff.
There are two major sub-branches -
Assault focuses on more planning and some Tank stuff.
Infiltration buffs Leg Infantry and gives bonuses to Night Attack (this, with the techs, can completely negate the penalty) and Recon (mirroring S&A).
Overall: Follow if you start with it. But be aware that massed Arty is basically a hard counter if the enemy is fielding more divisions than you are. It's not suitable for an outclassed nation, but it is suitable for one only slightly below average.
MASS ASSAULT
Main users: Russia, the Chinas.
Rush B. Erlin.
Mass Assault starts off with a bonus to reinforce rate (useful before you get radio) and divspam speed, Mass Assault is basically "keep the pressure up".
I see Mass Assault as a bit of a One Trick Pony. The first three parts are good - Supply Grace is something all other doctrines lack and more Entrenchment is never a bad thing - but then it splits into two very distinct branches.
The Deep Battle buffs Tanks. DO NOT TAKE THIS BRANCH AS CHINA UNTIL YOU GET A GOOD AMOUNT OF TANKS! The overall strategy is "wear them down with line infantry and then break through with Tanks" but this is only a good strat if you have twice as many divisions or more and plenty of manpower to spare.
Mass Mobilisation is quite short. But the Human Wave Offensive is the best part. The -0.4 Leg Infantry width applies to both branches, but here, with the Mass Charge and 5% Recruitable Population (remember that that's the same amount as Blitzkrieg... grr I hate that) and 15% reinforce rate, who's complaining?
Overall: If you have enough Manpower (No problem with either the Socialist Science National Focus or just being China) then it's good. It's also good if you take the Mass Mobilisation. But you need to have enough Infantry Equipment. And, IMO, it's good, but not great. Just as the description says.
Tl;dr:
Blitzkrieg rakes the power ratio and squares both sides
Superior Firepower fits Arty spam
Grand Battleplan is... turtling.
Mass Assault is decent but not great.
What do you think?
