The evolution guide (slimes included)

[Kesa]

It is possible to evolve earlier steps at lvl 100 but this is what you gain:

• 1* + 1* = 0.000125 = 0.0125% of these stats are carried over to your final hero
  
  
• 2* + 1* = 0.0025 = 0.25%
  
  
• 3* + 1* = 0.05 = 5.0%
  

I didn't understand about it

That is, if i evolve two heroes 100 lvl 1*, i get a 2* hero with an increase in characteristics of only 0.0125%?

What will be the percentage of increase in characteristics at the evolv of two 2* heroes? 3* + 3*?

Do i need to do this for perfect evolution:
((1 * + 1 *) + (1 * + 1 *)) + ((1 * + 1 *) + (1 * + 1 *)) (all heroes lvl 100)

or for perfect evolution this is enough
((1 * + 1 *) + 1 *) + 1 * (all heroes lvl 100)