How/Why does the 20% Refill only provide 10%?
Solution 1:
A similar question was asked here.
And Clamps (Bob Maestri) gave the following answer :
My first guess is that your attack and defense stats are too low to get the full 20% from the boosts. Please PM me your ID's and I will let you know.
If you keep on reading the conversation, you only get those 20% when your attack and defense stats are high enough, before that you get a lower percentage.