allow backslashing comma and space

[jidanni]

(info "(make) Syntax of Functions")
      Commas and unmatched parentheses or braces cannot appear in the text
   of an argument as written; leading spaces cannot appear in the text of
   the first argument as written.  These characters can be put into the
   argument value by variable substitution.  First define variables...

Good heavens. Why not just let "\ " mean space and "\," mean comma or
something? Or mention the reason for the "hoops" right there on the Info page.