I saw a huge difference in wr down flufiness between two vendors.
One came in 3oz bags was very easy to scoop / stuff & clumped up like you're describing. I hit my finished quilt with a tennis racquet which helped.
The other batch came from a dedicated down company in a pound bag. It is so fluffy & light that scooping was futile. That quilt is wonderfully poofy and is very satisfying. I had to wait a week for the down to ship because they had to dry the down but it was worth the wait.
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