I have used hold fasts for 40+ years never a poor hold. If the wood is soft pine it can deform, or if its to thin . Tops need to be about three inc. Plus if you do not have three in. You can glue and screw a thicker section along the dogs row. Also as George is showing you can add grip to the hold fast. Dimple it or run cuts around the shank. Care given not to over do it its a little goes a long way thing.
George good to see you back your wisdom was missed.
Frankj