remote hook -
There's a few guys doing it in UK, but it is a well-kept secret, and the positioning is done with mirrors if you're by yourself in a 350/355. I'm not so sure that the authorities like VR, but I don't think any of them have any skills in that direction anyway, not from the "real world" at any rate. There are one or two experienced guys teaching it, but again, it's not promoted too much. PM me if you want details.
To quote one company not a million miles from the North of Scotland (not PDG): "There's no requirement, so we don't use it." They've obviously never heard of being proactive and letting customers know it's available. Personally, stressing the fish with the downwash with a 30 ft strop is not a good idea, aside from being too close to the tanks.
We use it for putting poles in holes for 11 kv power lines, but we don't have holes in the floors of our Astars, and the line we use is 100 ft.
I have used a 75 ft line in Canada out of a TwinStar, and had to keep swinging the load so I could see it, but I prefer a 407/206L if I'm going to stick my head out of the door. Incidentally, even if you can't get your head all the way out in a 350, taking the doors off is still a good help with the peripheral vision.
As the man said, if you ain't got your head out of the door, it ain't longling, but vertical reference is a better term if you haven't got a ground crew or observer.