So the Potential System may be coming very very soon so I'm going to make a post explaining the system. If I get anything wrong, please feel free to correct me in the comments! Here we go:
First off, in order to even use the System, you will need to be rank 50 and have completed both stages of "Epic Showdown" and on all difficulties!
(Scroll to the next photo)
The overall design of the system is like a Skill Tree, just like in many RPG games you have played. There will be these nodes that increase your chosen unit's health, power and defense, individually. But there are bigger and more rewarding nodes in the Skill Tree known as Abilities. (Swipe to the third photo)
These abilities are Additional Attack, Critical Hit, Dodge, More Power against type advantage, More defense against type disadvantage, Stronger Super Attack and More Heatlh Recovery when collecting same type orbs as the unit collecting.
So far with my experience, you are allowed to get each one except Critical Attack and Dodge without a dupe. (But a few units cannot get Additional Attack without dupes) (Swipe to the fourth photo)
So once you gotten far enough into a path, you will notice this roadblock in the way. The ONLY way to bypass it, is if you have a DUPLICATE. Four dupes are needed to MAX out any one unit. (Swipe to the last photo)
Once you have gotten to the roadblock, you will notice that it shows the current units art, which means you need that exact same unit and it's same rarity to bypass it. But there's no need to dokkan the dupe all the way to TUR or LR. Once the System finally opens for everyone, the baba shop will be updated with a new item: an Hourglass. Hourglasses are used to REVERSE a unit's rarity and UNdokkan them! Which allows you to use the level 1 SA 1 UNdokkaned dupe to unlock a full path. Then once you have unlocked the path, you can go ahead and dokkan your unit back to its dokkaned form. Level, stats and SA will return to normal once you dokkan the unit. You do not need to gather any medals or zeni to reverse the reverse dokkan awakening. Although, one Hourglass costs 30 Treasure Gems!