Supercalls

If a call takes a "but" modifier and another call, it can be considered to be a "function" or "mathematical operator" on that other call. That makes it effectively the same as a concept. Such a usage is known as a "supercall".

Under normal circumstances, it doesn't make any difference whether one thinks of a call with a "but" modifier as a type of concept or not. People know how to do a Tandem Linear Cycle, and they know how to do a Tally Ho but Linear Cycle. Both are complex operations in which Linear Cycle plays a role.

However, when used with meta-concepts, the role of a supercall as a concept becomes very complex. Among the problems is that they are grammatically peculiar. The command "Initially Tally Ho but Flip Back" is hard to parse. Once one realizes that "Tally Ho but" is essentially a concept, one can apply the "Initially" meta-concept to it. So one applies "Tally Ho but" to the first part of Flip Back.

Tally Ho but Flip the Line 1/2
Scoot Back

Also, the order in which things are done can be quite non-intuitive. It is necessary to think carefully.

\sxvlines{g1w,b1w,b2e,g2e}	\sxhdiamonds{b2s,g1w,b3n,g4e}

before Finally Line to Line but 1/4 Wheel to a Diamond	after (Do the 1/4 Wheel first, and the diamond part at the very end.)

Supplemental Material:

Supercalls (Lynette Bellini)
Supercalls: A New Class of Concepts (Dan Neumann)
Star Wars: When Meta-Concepts and Supercalls Collide (Bill Heimann)