docs: explain lenient_comma_suffixes by its observable behavior

'Lenient initial-shaped test' was internal jargon. The flag decides
'John Smith, V': suffix (the fifth) by default, or given-initial V
when False; multi-letter suffixes are unaffected. Verified live both
ways before wording.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: derek73

docs/customize.rst

@@ -95,9 +95,11 @@ listed below.
        splits suffix groups and cannot be replaced.
    * - ``lenient_comma_suffixes``
      - ``bool``
-     - Allows a segment after a comma to be read as a suffix using
-       the lenient, initial-shaped test. Set ``False`` to require the
-       strict acronym form.
+     - Reads an initial-shaped suffix word after a comma as a suffix:
+       ``"John Smith, V"`` is John Smith the fifth when ``True``
+       (default); ``False`` reads ``V`` as a given-name initial
+       instead. Multi-letter suffixes (``III``, ``MD``) are
+       unaffected.
    * - ``strip_emoji``
      - ``bool``
      - Excludes emoji from tokenization — they appear in no field or

nameparser/_policy.py

@@ -101,8 +101,11 @@ class Policy:
     #: is structural (the same comma reading that parses
     #: "Family, Given" input), not a configurable delimiter.
     extra_suffix_delimiters: frozenset[str] = frozenset()
-    #: Allows a post-comma segment to read as a suffix via the lenient
-    #: initial-shaped test; False requires the strict acronym form.
+    #: Governs "Family, Suffix"-shaped input where the suffix word is
+    #: also initial-shaped: "John Smith, V" reads as John Smith the
+    #: fifth when True (the default, v1 behavior); False reads "V" as
+    #: a given-name initial instead (family "John Smith", given "V").
+    #: Multi-letter suffixes ("III", "MD") parse the same either way.
     lenient_comma_suffixes: bool = True
     #: Excludes emoji from tokenization: they appear in no token,
     #: field, or rendered view. The original string keeps them (input