message: Update preprocessor documentation.
diff: @@ -628,7 +628,8 @@ does not include a fully-featured Verilog preprocessor yet.)
  #### Strip Comments
  -Removing comments can be useful step in preparing to obfuscate code.
  +Removing comments can be useful for preparing to obfuscate code for sharing with
  +EDA tool vendors.
  ```shell
  $ verible-verilog-preprocessor strip-comments FILE
  @@ -638,7 +639,8 @@ This strips comments from a Verilog/SystemVerilog source file, _including_
  comments nested inside macro definition bodies and macro call arguments.
  Comments are actually replaced by an equal number of spaces (and newlines) to
  -preserve the byte offsets and line ranges of the original text.
  +preserve the byte offsets and line ranges of the original text. This makes it
  +easier to trace back diagnostics on obfuscated code back to the original code.
  ## Indexing Verible C++ Code using Kythe
  