Anchor manufacturers have always been conservative in their recommendations. Most will point out, if pressed, that even the best
anchor can drag in the wrong circumstances.
However, anchor designs have improved enormously over the recent years and the manufacturer of an anchor loosely based on the advanced Vryhof Stevpris design has made this rather far fetched claim. I remain sceptical, but make up your own mind. As always, I would recommend some caution.
The link below has some details:
Drag Free Anchor