Clarify that the PEP intent is not to serve as an

internationalization tool or to accommodate every
possible convention.  It intends to provide a
generally useful tool for improving readability in
many contexts.

Also, clarify the groupings are for the integer part
of a number.  Digits to the right of the decimal point
are unchanged.

pep-0378.txt

@@ -35,7 +35,8 @@ in detail.
 
 .. _`many other challenges`:  http://docs.python.org/library/locale.html#background-details-hints-tips-and-caveats
 
-It is not the goal to replace the locale module or to
+It is not the goal to replace the locale module, to perform
+internationalization takes, or
 accommodate every possible convention.  Such tasks are better
 suited to robust tools like `Babel`_ . Instead, our goal is to
 make a common, everyday task easier for many users.
@@ -59,12 +60,6 @@ Research so far
 Scanning the web, I've found that thousands separators are
 usually one of COMMA, DOT, SPACE, APOSTROPHE or UNDERSCORE.  
 
-James Knight observed that Indian/Pakistani numbering systems
-group by hundreds.   Ben Finney noted that Chinese group by
-ten-thousands.  Eric Smith pointed-out that these are already
-handled by the "n" specifier in the locale module (albeit only
-for integers).
-
 Visual Basic and its brethren (like `MS Excel`_) use a completely
 different style and have ultra-flexible custom format
 specifiers like::
@@ -158,7 +153,10 @@ Examples::
   format(1234, "8_d")      -->    '   1_234'
 
 This proposal meets mosts needs, but it comes at the expense
-of being a little more complicated to learn and remember.
+of taking a bit more effort to parse.  Not every possible
+convention is covered, but at least one of the options (spaces
+or underscores) should be readable, understandable, and useful
+to folks from many diverse backgrounds.
 
 As shown in the examples, the *width* argument means the total
 length including the thousands separators and decimal separators.
@@ -220,6 +218,21 @@ Commentary
   is to set the convention once and have it apply everywhere (others
   commented that locale already provides a way to do this).                                                              
 
+* There are some precedents for grouping digits in the fractional
+  part of a floating point number, but this PEP does not venture into
+  that territory.  Only digits to the left of the decimal point are
+  grouped.  This does not preclude future extensions; it just focuses
+  on a single, generally useful extension to the formatting language.
+
+* James Knight observed that Indian/Pakistani numbering systems
+  group by hundreds.   Ben Finney noted that Chinese group by
+  ten-thousands.  Eric Smith pointed-out that these are already
+  handled by the "n" specifier in the locale module (albeit only
+  for integers).  This PEP does not attempt to support all of those
+  possibilities.  It focuees on a single, relatively common grouping
+  convention that offers a quick way to improve readability in many
+  (though not all) contexts.
+
 
 Copyright
 =========