Please clarify...Armor Break and True Damage

Has someone tested with champs with Armor break and attacks dealing true damage (e.g. Ronan, Thor, etc.). If negative armor due to stacked armor breaks is not possible with diminishing returns, attacks dealing true damage on armor broken champs will yield the same damage? Is this correct? So for Ronan’s case, it would be better to perform his specials against armor buffed champs rather than breaking the enemy’s armor before doing his specials (via heavy attack).
0