There seem to be diffrent tiers of perks or values assigned to perks.
Once I reloaded the same save a lot of times to look at what perks my survivors get:(dont fix me on this I've lost the notes on my inspection)
tier 1 (low value): Artist, Firearms Training, Good Cook, Bookworm
tier 2: Redecorator, Melee Training, Hoarder, First Aid
tier 3 (high value): Tools Expert, Hand To Hand, Green Thumb
Perks like Fearless Reclaim seem to be something like 4 or 5 (highest value Ive seen),
The Faction perks (former blabla increases sway..) seem to be less valuable than (5 training related) perks like Fearless Reclaim, Commander, MacGyver, Scrapper
Special Perks like Stinky, Brave or Loner (which are not awarded for training in a skill, but by career, more on that below) seem to offer a lower value for stuff like Fearless Reclaim to appear more often.
Other Special Perks (I'm calling everything out of the 5 training fields "Special Perks"), that are beneficial (like Half Rations, Friendly etc.) seem to have a value between tier 1 and 2
Awesome Special Perks (like Superman, Ninja) seem to have a similar value to the tier 4 (tier 5) training related perks
concluding:
-if a survivor has low value perks like Artist and Stinky he is more likely to get higher level perks like Fearless Reclaim.
-if a survivor would (look at the perk options and reload a save before you looked to see this) get the option to choose Fearless Reclaim (he is a builder with low value perks) and you train him to be something diffrent, like a fighter he gets the perk of the other training (here: Commander)
-Special Perks are only obtainable from the careers, while every of the training groups has 4 perks assigned to it (like: Good Cook, Hoarder, Green Thumb, Scrapper)
-there are perks to increase a training stat by 3 (Fighter, Resourceful, Genius, Handyman, Born Leader), which have a higher value as well (undetermined, but above or equal to 3), not sure how they are triggered (somehow has to do with careers)
-some careers have 3 and some have 4 perks (one of the 4 being a high value special perk only showing up, when the value of 2 taken perks is low enough (always as the last perk))
-it is impossible to get more than one of the super-perks like tier 4 (tier 5) training-perks or awesome special perks.
-some careers seem to have a higher cap for the total value of perks you could get, meaning they are unable to obtain super-perks
A list of all perks and their corresponding Id's can be found on a post in the general discussion about the game on Steam called "Perk Debugs?":
https://steamcommunity.com/app/257170/d ... 839584070/Ok stumbled upon this, which explains it better:
viewtopic.php?f=2&t=2005