Mmmm interesting, I'm sure my flocked dual trims have flocked inners too? Doesn't matter, it feels like a good scrubber if you know what i mean.
Your brush may have flocked inner bristles now, but when they were new they would not have looked like this.
To make flocked/flagged bristles an agent is mixed with the bristles material in manufacturing which then allow the bristle end to 'fray' when crushed. The bristles are then cut to length, folded in half and crushed at the tips to make flagged/flocked bristle tips.
The inner shorter non-flocked bristles on the Super-Lite Flocked DT brush are made from the same material as the outer bristle, but just not had the tips crushed. However with a few months of use the tips will start to soften and fray slightly giving a more flocked appearance.