Almost everybody said that COAM didn't exist long before Page 39, Gordy appears to be hanging out there on his own still.You do not need to build a model to say that CoAM does not exist.Torsten gave the reasons why in his post Page 39 #382.
You were looking at the wrong slice of time. I asked for a birds eye view of the cast based on practical trials and casting experience, the birds eye view confirmed the observed rise in line speed. Your model outcome is nowhere near Graeme's tracker plot.I denied the rise in speed because it is not supported by Graeme’s data (see Page 38 post #371) and since this is not an outcome of the model.
The late rise in speed coincides with a large rise in rod leg tension and is not typical unless you throw a good cast into the overhang, you don't see it with the same lines if you don't go well into the overhang. Most lines accelerate later and at a lower rate in the cast.The late rise in speed you show in some posts is typical of a level line at the end of the rollover (typical taper of sinking tips). Without some taper and / or a leader the line is likely going to kick back, nearly all lines accelerate at the end of their rollover (observed by Graeme incidentally). Only light lines with a rather large loop may not show an acceleration.
It has nothing to do with pullback, I introduced that concept into the discussion to try and help you understand the behaviour of the abrupt change of rod leg tension, because you cannot make the cast yourself. In a tethered cast, the change in rod leg tension when the slack is taken up with a multi density line is much more abrupt than pullback.I think you focus too much on what can happen with a pullback, a change in line density is not equivalent to a pullback in terms of physics. If I can find some day a technical reason and a mean to adapt the model for a speed change during or just after transition, I shall do it.
It appears to me that there is a blind spot in your models with respect to rod leg tension, I recall a similar discussion with the bouncing bomb casts lifting the rod leg off the ground. If you hit an abrupt stop, N3 comes into play between the rod and line, this is exactly the same.If I can find some day a technical reason and a mean to adapt the model for a speed change during or just after transition, I shall do it.
Vince