|CaptnB Goblin Squad Member|
The only level of training you will need to care about is that which is produced by your own Settlement
Not quite, there is a system in place to support feats you can't train in a settlement. Here's a quick example with encumbrance feats:
NPC settlement : Training = 0, Support = 4 (you cannot train them at all but if you train them elsewhere, the settlement will let you use it up to level 4)
Crafting Settlement : Training = Support > 4. I don't know what the higher level is but if you live there, you'll be able to both train encumbrance and use it at its max level.
Also, when I looked at encumbrance 5, there was an extra line in the tooltip saying that my NPC settlement was not supporting it.