Behavior of "edit" command

[Daniel J Sebald]

I'm curious people's thoughts on the behavior of "edit".  "edit" is a 
command I never used much because I'm somewhat command-line oriented and 
will just do a "gvim" from the shell instead of an "edit" from the 
Octave command line.

The way "edit" works is it will open the specified file for editing.  If 
the file in question is not editable because it is an Octave system 
script, for example, edit will duplicate that file and place the copy in 
the first directory in the user's Octave path.  That is convenient, if 
that is what someone wants to do.

On the other hand, with the new GUI/IDE, that often isn't what one wants 
to do, at least for developers.  For example, I was looking at a 
plotting bug and just wanted to see what the Octave scripts are doing so 
I thought I'd place some breakpoints in the code.  A fast way to open 
the file, I thought, would be to do:

edit plot
edit image

and then place a breakpoint.  But that is duplicating the script file in 
my <home>/octave subdirectory, which isn't something I wanted.  I then 
have to delete the files that are duplicated, otherwise updates to the 
system scripts won't take effect.  Octave has gotten to the point where 
I no longer have customized, common scripts.

Could edit have some options for duplicating or not duplicating a file? 
 Could there be a "debug" command that will stop at the first valid 
line in any used script files?  E.g.,

debug("plot (1:50);")

If that were to open the plot.m script, one could then at least "step" 
and "step into" to move about.  Or is this simply a problem I'm 
experiencing because I'm not setting up my development tree (via 
./run-octave) or system installation in a nice way?

Dan