Intelligence effect on beneficial spells

In the talent list on level up, the "supporting" ones, the last two, in german "Wundpflege" und "Feldlazarett".

The text says 99,5 HP over 13,5 sec (base 9 sec)

They have a base time of 9 sec, my char has 20 Int and thus a longer spell duration. So is this really better? Is this correct?

And what does it mean? Does it heal more? 13,5/9 * 99,2 HP? Does it heal the same but slower? Or is the text just plain wrong and the time should be multiplied by (1 - int bonus) instead of (1 + int bonus)?