I know folks who can cast into the backing; I'm not one of them. They don't carry the backing in the air, but rather "shoot" the line which pulls the backing along. Normal fly line are around 90 feet in length and I've seen good casters reach 135 feet or more, so do the math.
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Dan S
"I still don't know why I fish or why other men fish, except that we like it and it makes us think and feel." Roderick Haig-Brown, A River Never Sleeps
Dan S
"I still don't know why I fish or why other men fish, except that we like it and it makes us think and feel." Roderick Haig-Brown, A River Never Sleeps