"Here is something you may not know. Healing is one skill that goes past +5 so if your hero has +5 and you have an item with +5 you get +10 healing so you can heal more than normal." - KGB
Maybe it would be worth entering this information in the game? I didn't know about that either:unsure:

Not sure where I could enter that in the game because there isn't a general description for all the powers. That only existed in the manual.

KGB

Meybe in central game screen: Help - Topic Skills (A-H) - Item Heal?