Why do the a buffed coking plant different from all other buldings?

[MadM4n]

Today I realized that buffed cokingplant is different from all other buildings when it is buffed. All other buildings I have takes the same amount in but double the output, but not the cokingplant?! It doubles all. So a lvl 1 plant unbuffed takes 1 log and makes 1 coal, a buffed takes 2 logs and makes 2 coal. No other building, what I can find, do like this. Is this a bug?

[Sinister-King]

Hi MadM4n,

A level 1 coking plant uses 2 pine wood to produce 1 coal unbuffed :).

[MadM4n]

Hi MadM4n,

A level 1 coking plant uses 2 pine wood to produce 1 coal unbuffed :).

Now I feel stupid. lol. I tryed 2 ask in the helpchat, but no-one said that. lol