[tex-eplain] Drawing leaders using \gridcommdiag macro

[Guy Worthington]

I wrote
>Has anyone developed a parametric method of drawing leaders in
>diagrams?
John culleton <john@wexfordpress.com> replied
> [snipped] perhaps pstricks or xfig might be appropriate.

Thanks for the tip John,  

I blew the dust off "The LaTeX Graphics Companion", and am
reading the chapter on PSTricks.  The only firm conclusion 
I've drawn so far is that whoever wrote this chapter and 
the guy who wrote the book of REVELATIONS attended the same
course in creative writing...come to think of it so did Knuth,
Kernighan, Norvig, and Von Neumann.  Perhaps Seminal works 501
with keynote speaker St John the Divine.

There's got to be a simpler way to chuck a box around some text
and point to it with a couple of arrows and let TeX look after
details.