Is Tradition Magic's Increased Immuto cost per type or instance?

[diki]

Tradition Magic applies a TN +1 penatly for adding alteration Immutos.
I think it's unclear if this is for each type of Immuto or for multiple instances of the same Immuto.
For example the reduce damage and reduce resistance both have a TN - 1 effect.

Does a follower of Tradition Magic ever gain a benefit to appying these Immuto. If they used reduced resistance 4 times would they get TN0 or TN-3 (TN-4 + TN+1)?

Obviously a Fatemaster can decide for their game, but I wanted to understand the intended design.

[Mason]

"Each time this character adds an Alteration Immuto other than the chosen Immuto to a Spell or Manifested Power, increase its TN by +1."

The penalty is per instance of the Immuto.

If you add the Increased Damage Immuto once, the damage of the spell increases, and the TN of the spell increases by +2, plus an additional +1 from your Tradition Magic.

If you then add the Increased Damage Immuto a second time, the damage of the spell increases again, and the TN of the spell increases by another +2, plus an additional +1 from your Tradition Magic.

Thus, a character that adds two Increased Damage Immutos to her Spell would have its TN increased by +4, or by +6 if she used Tradition Magic (unless, of course, she chose Increased Damage as her special Immuto, but let's assume that she did not).