Spey of course!
Yes, I'm talking spey casting. Sorry I didn't memtion in it up front. Thought very one understood there is only spey casting left in the world. I've been working with a double taper line to get my technique down. So my limits are 70' cast up to 80' using a DT. What I've discovered is the line jumps (super charge effect) off the tip. I've yet to try shooting 100' to 110' foot cast with a head. The "kick-back" (with bottom hand) is very, very small. To much kick-back and the line just off the tip does a dealt shape loop and settles to the water in that dealt shape. My theory is: a solid, conscious stop with the bottom hand makes the tip unfold with greater energy, BUT not a reverse of the butt. I don't think the tip does the snap-t thing. The tip just unloads faster. Hopes this helps in explaining what I'm attempting.
When the fish gods smile, I smile too!