White tea is oxidized naturally for a while. The article is referring to freshly picked leaves.
He was also adamant about storing it in well sealed containers out of direct sunlight. I ended up throwing away a couple of containers because of this (although I've kept a couple that are just too beautiful to part with - I store my daily drinker in there since it doesn't need to keep as long). Also explains why my dealer uses mylar vacuum packs for anything over an ounce. No oxygen, no light.
"Total catechin content (TCC) for white teas ranged widely from 14.40 to 369.60 mg/g of dry plant material for water extracts and 47.16 to 163.94 mg/g for methanol extracts. TCC for green teas also ranged more than 10-fold, from 21.38 to 228.20 mg/g of dry plant material for water extracts and 32.23 to 141.24 mg/g for methanol extracts."