One observation I've made is that the hauling hand in the 'turbo spey' as Simon calls it actually shortens the d-loop length needed for reasonable casts, when coupled with a follow-thru extension of the arm the rod gets a lot of flex fore vs. aft and is a real honey of a cast. I use it frequently even on the flats in my short game as well as stream fishing.
Because of static surface tension from the line laying on the water at the end of the first move of the double spey this cast typically requires a pronounced d-loop such that the end of the leader and the fly pirouettes to face the shore before a proper load can be attained. This is not a concern for short casts, but if any significant distance is desired it's critical.
The snake does not suffer from this particular problem but because the aerial coil needs a good grip to create a momentary tension against it's difficult at best to make much of a cast with zero backcasting room, if not impossible unless the angle change is minimal.
But if you are only casting 30ft of line well all bets are off. As much as I did enjoy the show you two have convinced me it wasn't the only way to have mid-winter fun.
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