Originally Posted by JoJer
The line will shoot where ever the rod tip points last (per L. Kreh). Your back cast doesn't have to be directly opposite where you want to send the fly. If you're hanging up in trees behind you, change your backcast so it shoots up instead of back.
Any cast where the two limbs of cast are at less than 180 degrees can lead to a tailing loop. So if you make a standard high backcast followed by the forward cast at less than 180 degrees, you can get crossing and tangling of the fly and rod legs of the loop. This type of cast is called a steeple cast.
"7. Trying to cast the backcast and forward cast at an angle of less than 180 degrees [in the plane of the rod]
I'm running out of succinct definitions. Make a high backcast, then make a high forward cast and your loop will tail. Why? Dumb question, the tip has dipped beneath the Straight Line Path. Of course there are times when it's the only option: just to give you a feel for this, a vertically orientated Steeple Cast has a backcast/forward cast angle of considerably less than 180 degrees. And that's why it sucks of course."
Tailing Loops - description and cure
A way to minimize tangling of lines is to widen the loop formation AND to separate the high backcast and forward cast horizontally. For a tailing loop to form a "wind knot" the two legs of the loop must form in the same plane. If you do a bit of an oval cast by tilting the rod to the side on the back cast and bringing it overhead in the forward cast, you can separate the two legs a bit horizontally so they will not tangle.
Watch the video below. When he is facing you stop the action and he makes the forward cast and you will see that the fly leg of the loop is OFFSET to the right side of the caster compared to the rod leg of the loop. This is the HORIZONTAL separation you get with the rod tilt on the backcast and the overhead forward cast.
In the video below there is a bit of trickery going on some of the casts. Notice that when he turns sideways and makes the high backcast, on some of the casts, he delays a bit until the backcast falls lower before making the forward cast. If he did that with a tree behind him, the backcast would hit the tree before he begins the forward cast. The delay allows him to avoid a tailing loop.
Timing and a convex rod tip path to form an open loop are also keys to prevent hitting a tree on the backcast and avoiding a tiling loop.