Bill,

The essential fact of control-line IS the tether. Sure, it's not a spike with a swivel stuck into the ground... WE are the center anchor.

The difference between "disciplines" (RC & CL) was very nicely stated a few posts above this one of yours. IMHO, CL is a more complex flight-force environment than FF or RC, BECAUSE of the tether (our flying lines). The forces involved do not exist in "free-fllying" - controlled or otherwise. Also, most of us in CL do not have trimmable power, roll or yaw while in flight. (Carrier and Scale being the usual exceptions, rarely seen as a sport/fun effort, tho.)

The limited flight radius (that almost all of us accept ) is another big difference from free-sky flying. We most often want our CL model to fly in a flat skid on a radius 20 times wingspan or less. I've seen RC fliers try to make a point by flying, say, a .40-type trainer in about a 60' radius circle, not too high above ground. That required a severe bank angle, and prudence urged that the RC guy try to keep as many of the "3 mistakes high" altitude as possible.

We never get three mistakes high. We never get out of 'ground chop' ambient air conditions. We never can trim up for a cross-wind for two reasons: NO in-flight trim gismos, and we confront the wind from all angles, EVERY LAP. Stunting adds some vertical trig to that picture, too. We can never really ease out to grab some sky and let the plane figure out how to save our bacon, or other groceries.

...Because we hold one end of that special tether that makes CL such a lasting enjoyment for many of us. Mentioned in this thread, too, are the required control forces for the necessarily tight maneuvering we can squeeze into that limited hemisphere. The speed and power of very large RC servos might approach some gentle CL maneuvering load requirements...

Sometimes, while I'm enjoying a CL flight, or perhaps a bel canto Opera, the thought appears: Why should these pleasures be changed only because we have technologies that CAN change them. Another less often mentioned aspect of difference between RC and CL is that CL is PRIMARILY tactile, while RC is primarily visual. There are the zero-lag instinctive, correct, learned physical reactions in CL, and the "see/analyze/choose/react/evaluate the result/back to item one" aspect of RC, which can be run through very quickly, if enough effort is put into it. Unfortunately, to me a transmitter still feels the same whether it is on or off, and something like a cigar box rigged with a couple of Q-Tips and rubber bands... A CL handle, however....

Not knocking your comment, just sharing our joy at holding the leash on a spirited, mostly tamed tiger.