Up in striper country a 7/32 brass eye on a light wire high quality 1/0 hook with 6" of material is easy to make ride correctly if you tie the materials on right. I am not reluctant to pay $15 for 25 TMC 811s because they deliver on the promise - light and super tough. I've noticed that where I once had friendly debates about this hook for striper flies the have become the standard lately especially for flats flies like deep eels.
The high ratio of materials to metal makes them cast well and land pretty softly compared to standard clousers (big lead eyes and little material) or epoxy based flies. Sometimes a big splash is an attractant but rarely on a shallow mid-day flat.
I also catch a lot of fish on unweighted bonefish flies down in the tropics but it applies to slower water and shallower presentation. I have a scintilla dubbed pattern that is a summer steelhead fly with a very light hook that lands like a feather in a crowd of tailers without spooking them. It sinks slowly so I have more time to entice the nose-down bones. I don't think it has as much to do with the hook showing than the fact that the fish are in a sedentary grubbing and tailing mode and the fly permits stealth and slow sinking attraction among them. Next time down I will have some tied gawdy with the same light design and see what they do. I am confident that it's the presentation not the flash. I have filmed gobies and other flats morsels bones like and they look just like a pearly flashy gotcha right down to the little bands of pearly silver on the sides.
Current and depth are key factors, typically I've found while fishing a slow sinking fly mid-day in fast current that stripers are not prone to eat. The distance to lead the fish in fast current is excruciatingly far and they change directions a lot, not to mention they won't come upward for something over their head very often at noon.
With a hook up fly I can lead them and let the fly settle while the fish advances, adjusting as they come to put the fly into their kill zone. With a hook down I often caught shells, rocks, or weed in the pause.
In soft water like at the top of the flood in the end of an approach channel (e.g. up in the grass) an unweighted slow sink fly gets the nod.
Surface feeding fish are another story entirely, where's my popper!
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