Unofficial Fallout 4 Patch

The descriptions for ranks 1-3 of this perk are as follows:
- You've learned to split the atom... and command it. Radiation weapons do 50% more damage and Fusion Cores last an extra 25% longer.
- Radiation weapons now do double damage and Fusion Cores last an extra 50% longer.
- Fusion Cores can be ejected from Power Armor like devastating grenades and Fusion Cores last twice as long.

This is not representative of the perk's actual effects on fusion core drain rate with regards to power armor.

Rank 1 of this perk does the following:
* adds two perk entry points via "Mod Spell Magnitude" and "Mod Typed Weapon Attack Damage" to increase radiation damage (not relevant here)
* adds an ability to the player, AbPerkNuclearPhysicist
* adds a perk entry point via "Mod Ammo Health Mult"

The "Mod Ammo Health Mult" entry point sets Mod Ammo Health Mult to 1.25 on the condition that the player doesn't have NuclearPhysicist02, and WornHasKeyword ArmorTypePower, or WornHasKeyword ma_GatlingLaser. The first interesting thing here is that the "Mod Ammo Health Mult" entry point has no effect on power armor core drain rate (which I tested), so its inclusion in the conditions list serves no purpose other than to be confusing, and potentially cause bugs with mods that add new "healthed" ammo types that work similar to Fusion Cores (e.g. a new weapon using a new ammo type with the same health mechanic would be able to fire more shots per unit of ammunition while the player is wearing power armor than outside of it with this perk active).

The second thing to look at is the ability AbPerkNuclearPhysicist. This adds a spell effect "ReducePABatteryDamageRateEffect", that reduces drain by 33% if the player does not have perk NuclearPhysicist02, and by 50% if the player does.

Rank 2 again does the radiation damage thing, and again adds "Mod Ammo Health Mult" with the unnecessary check for WornHasKeyword ArmorTypePower. The Mod Ammo Health Mult entry point also does not check whether the player has NuclearPhysicist03 (as 01 does for 02), which means that at rank 3, the effect for both rank 2 and 3 are active (both using "set" functions), though this isn't usually a problem since the rank 3 perk is added later, so its effect overrides the earlier one.

Rank 3 also adds "Mod Ammo Health Mult" with the same unnecessary WornHasKeyword ArmorTypePower check, and as mentioned before technically conflicts with rank 2's effects because of rank 2's missing check for rank 3.

So, to summarize:
* Rank 1 increases Power Armor fusion core lifespan to a total of 149% (not the listed 125%)
* Rank 2 increases PA fusion core lifespan to 200% (not the listed 150%)
* Rank 3 does not actually affect PA fusion core lifespan
* All ranks erroneously apply their "Mod Ammo Health Mult" entry point when the player is in Power Armor, which serves no purpose
* The "Mod Ammo Health Mult" entry point for rank 2 applies simultaneously with the same entry point for rank 3 because of a missing check, which has the potential to cause a difficult-to-diagnose bug based on perk order