A clickbar is something you click, which then runs a mapped key.
So it is a mouse click activated mapped key, instead of a key press activated mapped key.

A Repeater Region is straight mouse broadcasting, from any window to the recipients of your choice.
Clique + Grid or Vuhdo or Healbot interpret the click as an instruction to cast a given spell.
At whatever target frame the mouse is in or on top of.

So with the Repeater Region + Addon, I have no mapped keys for heals.
The addon interprets the clicks.
It works as well for five, ten, fifteen or twenty-man raids.