email conversation with brewer at St Bernadus

I emailed St Bernadus brewery to ask them about their dark candy syrup and how it gives the beer complexity. He told me that all of the complexity comes from the yeast and the yeast condition. He also told me that I am using too much dark candy syrup in my recipes. I use D-90 and D-180 usually 10% to 15% of fermentable. He said use 1% this doesn’t seem correct to me. I know that according to brew like a monk the use Pilsner and debittered black malt with light and dark candy syrup. If they only use 1% dark syrup how do they get all of those flavors in the 12?

Maybe he's thinking 1 percent total, like water volume included? I have no idea, perhaps ask him to clarify?