No Hermit, my reply was similar. My gundog (who is trained for his own amusement on dummies) would, if sent , go into a sea like that to retrieve something. The natural instinct to retrieve is so strong and of course when trained to a high standard they will go where they are asked. Although gundogs really enjoy their work, just as a collie enjoys working and they are undoubtedly hardy, that to me looks too dangerous.I know my father would never have asked his dogs to go in there.
Keep my dog at heel when near rough seas because he loves water so much that he would venture in and always think it would be so easy for them to become exhausted.