There are those who respond and dont respond to anything. I think that everyone responds to creatine, its more of a size of response. If you only gain 1kg of size, it may not mean that mcuh overall, I gain 2kg usually going on creatine, others gain 0,5kg, a large variability.
Creatine will aid whether you show a measureable response or not (immediate gains are easy to see, long term gains tend to be obscured by normal variation.