Chain Breaker - New Mechanics?

So Lethal Pride/Chain Breaker has changed.

It used to say:

Increases and Reductions to Mana Regeneration apply to Rage Regeneration.

Now it says:

1 Rage Regenerated for every 25 Mana Regeneration per second.

Does anyone know if this a "hard" number it's asking for now?

That's a very specific number it's asking for, which is throwing my brain off.

Meaning only a flat mana regen applies now, like an Aura of Clarity or Praxis ring?

Wiki is not updated on it new worded meaning yet.

Any clues?