He takes a broad view; it also helps convince me of why I love the less stiff / more progressive action which allows me to feel the load increase to the apex of power at the point of release in a semi-relaxed yet positive manner.
The stiff rods that work so well for some people just don't equate to casting pleasure to me, his description sounds twitchy, almost spastic to my perspective of casting (although I can get very spastic at times!). Meanwhile it's perfectly natural and the right method for many others, and furthermore people change as they experiment and I might be eating these words someday
Using very high modulus materials in well articulated tapers a rod can simply do the work for the caster. Certainly stiff rods require the caster to work harder, but that sense of active involvement can the definition of pleasure to others, it's a matter of preference I'd guess. For me I love to feel like I am working in symphony with the rod and line motions, without having to really think too hard about it so the river can join in on the chorus and the fish might even come by to do a little solo.
"Stiff" does not equal "fast" to me. I guess you could say that casting is the bending of a lever to create potential energy (load) and the transfer of that energy into a line loop form to project it out there. Fast is, to me, a way of describing the line speed that the rod generates comfortably based on (a) ease of loading (b) recovery and transfer of this energy into the line (c) ease of accelerating the stroke into a lightning bolt of a loop. Certainly a fast rod does not have to be a stiff rod, in fact in my opinion the ultimate rod is the rod that generates high line speed without high effort, i.e. "not stiff but fast".
Is this possible? Who knows, I ain't no expurt - but this is subjective as we established above. However I do know what I like and so does flytyer and there is no wrong or right just preference as Tim put it. Perhaps some phyics and physiologics too.
But my perspective comes from casting a stiff rod with too light of a line and finding it very difficult to load the rod and thus make a good cast unless the caster really works his ass off to bend the rod. The resulting loop from a comfortable amount of effort has no line speed or power - this is what people experience when they say the "rod is not loading".
If a more progressive smoother flexing action rod with the same grain carrying capacity was used with the same line, the caster would be much more able to feel the loading of the line and albeit it would still be too light to generate adequate load and line speed it would sure feel better, and fish better. In the end I fish to feel better, and feel it to fish better. Starting to sound like Tim there!
I've been spending a lot more time with extended belly lines lately and have been getting more comfortable with them than in the past. Strangely I have come to love casting them
But other than the brief instant where the compression occurs between the grip and the already forward moving loop there is nothing really explosive about long belly casting, at least the way I have adapted to move the mega-grain anaconda out there with my average body frame.
First of all the lift is painfully slow or it fails, as is the sweep to D-loop which is a patient slow gliide to a d-loop that takes forever to materialize. The key for me was to adapt to the different feedback you get from a loop that is still very much moving backwards and start forward so that the forward stroke will not be too late by the time yo anaconda hits the water; letting the already-in-progress forward momentum compress against the anchor almost on it's own out there and follow it thru.
When everything is matched up it becomes effortless, it's all about timing. With these extended belly lines I find myself doing much better by slowing down and paying very close attention to timing, and that works much better for me by using a longer rod with a will to flex (willing taper) for me yet recovers very fast (high modulus).
I also prefer a comparatively lighter line (Rio's A classification). For instance, on a 14ft 9/10 Custom I like the Grandspey or XLT 7/8.
I prefer a rod that is very accomodating for the slowing down of things like lift and sweep - but has ample modulus and power to compress the final power stroke.
I think the best all-around action is a balance between the will to get bent for the caster and the want to recover quickly - just like a vaulting pole. If the pole vaulter didn't get that huge bend he would not be able to propel over the bar. If he increased the modulus of the pole material while using a taper to allow him to bend the lever, he might end up on the ceiling.
Just a bunch of theory, but certainly fun to discuss. I hope others join in on this discussion with their experiences.