Busrt of phisical damage: Silk vs Spot

JhonST33

Let's compare the burst of phisical damage of this two champions.

Silk places a 280 phisical vulnerability debuff on each attack (basic or special), so at 14 debuffs, she lower the phisical resistence to 3920, which asemejated to the 3900 phisical vulnerability debuff placed by Spot.

Now let's see the burst of phisical damage at 14 debuffs:

She make a total of 14829 of phisical damage, in her habilites is stated that she makes a total of 7087, so, this is 109% more damage than the stated in her habilities. There is no furies or other effects that increased the potency of the burst phisical damage.
Now, let's see what happens with Spot.
He increased the phisical vulnerability at 3900 when activates the sp2 while in untouching, this is stated in his habilites.

As you can see, even if the opponent is below the phisical vulnerability debuff, he do exactly the same damage.
What do you think of this?

JhonST33

This imagen complements the imagen above.