Further to this (see what I did there) it can also pay to have a bit of extra line off the reel to feed into the cast as it drops down onto the surface. If you don't do this as the line falls it (and the flies) get pulled back towards you. This does two things, firstly it robs you of a bit of distance and secondly it means the flies hit the water already moving towards you. With really high banks this effect can move the flies a yard or two. If you are fishing dry obviously the last thing you want (99% of the time) is drag on the fly as it lands. Even if fishing wets and pulling you often get a rise as soon as the flies land in the half second before you start pulling. I don't know why but wet flies that hit the water already moving are not as appealing as ones that are static for a split second. This is odd because once you start pulling them on the retrieve the fish like them well enough. I used to do quite a bit of fishing on lochs with high banks and saw this happen many times. I'm convinced all flies should lie still for a second or so to give nearby fish time to nail them like any other natural fly that has fallen on the water.
I used to see an extreme example of this when I was on the oars. Some people were in such a hurry to start the retrieve, particularly on windy days with a fast drift, that they would start pulling a fraction of a second before the flies had hit the water. This would result in the flies hitting the water already furrowing and they NEVER got a rise as the flies hit the water like this.
Andy
