It is all explained in the article. You just need to read it.
Wildhorn - true, the article uses the example of Leather Gloves, but the token reads "Armor +1" and there are plenty of other effects that give armour +1 without requiring it to be linked to another source of armour. It seemed worth clarifying whether the author just used the Leather Gloves as an example for simplicity or whether the rules required it.
sIKE - thanks! That clears it up nicely.
If you read correctly you will see it clearly say that you can increase the armor of an equipment that as already armor.