Q: Why does a cast “collapse” if the casting stroke is started before the previous loop has straightened?

[flyfisher666]

If the rodleg/straight line have some negative velocity when the forward stroke starts, then there could be a "kinetic capture" I agree.

But pulling line through the loop is never going to give a higher linespeed in the end of the forward stroke.
There is atleast one possible benefit though - slack prevention.
I use it to some degree, especially in strong tailwinds.

//Joakim

[Dirk le Roux]

A favourite of mine over the last few months have been John Goddard's "half-a-backcast". The way I do it is like a sideways-starting Belgian PUALD cast emphasizing backcast laziness. It feels like before you "go" on the forward cast, the line simply sits up in a wide, airborne arc. Apart from its obvious fishing utility, this cast teaches me to maintain slight but continuous tension leading smoothly into the shot, unrushed acceleration and how to feel for readiness to "hit it".

Now, sweeping arc, slow backcasts are not quite what this question is about, so what of a narrower loop, more "conventional" cast? I have been experimenting with very early stroke starts on such type of cast during practice sessions since this topic started. Mostly I can make quite a good shoot, even when the forward stroke finishes around the time the fly turns around from the backcast (I let the fly crack there to confirm the timing audibly).

Less often, I manage to generate that collapse feeling, and when I do, it feels like I have mistimed acceleration rather than stroke start/end. The effect in such cases feels much similar to whenever the line have clipped an obstacle behind. I suspect, and this is purely intuition which may be far off, there is another dynamic at play, one of acceleration being out of sync with the line's centre of mass' motion at the time.

Cheers,
Dirk

[Dirk le Roux]

Oh, and I just confirmed again - it is easy enough to make a similar collapse starting the forward stroke with an unrolled line behind

So I think it is acceleration timing more than being out of sync with the centre of mass motion. That and possibly a bump in the fly leg (making the leader go vertical at the end) which I shall have to film.

[Paul Arden]

Yes that’s an interesting cast Dirk. I often aerielise all the Spey Casting anchors, which is a similar concept. In fact one of the older uses of the term Switch Cast was to mean a fully aerielised Single Spey. But everything can be aerielised with practise and care. You sacrifice a little in distance, but fishing wise there are lots of benefits. I’ve integrated many of them into Snakehead Shots.

Mel said it took quite a long time to make that segment of the video

Cheers, Paul