With the right dog they will hold on.
My first GWP was run with a pack of foxing terriers. She was a hard dog and would take no messing from anything. Would pull a fallow deer even if it was not shot.
Second GWP completely different end of the scale. Very kind gentle , would track a deer but would not engage in anything physical. I moved her over to work with my Harris hawk which she was great at.
Third GWP and current one- if she had been my first GWP it would have been my last.

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Great for tracking deer, will indicate deer bedded down in front of me. If tracking off long lead she has a GPS collar on her as she will keep running. - I can’t trust this one fully off lead when stalking if muntjac are around as she goes deaf and it may as well be someone else’s dog, I think this is from starting her to young.
All were broken to livestock as I have regularly access to free run my dogs through sheep, cattle horses on a daily basis.