If a client wishes to display timestamps to the user in local time, the client SHOULD perform the translation.

Is the previous sentence necessary?

No. - dave

• We already specify timezones must be provided as "Z" (UTC) times, is it really necessary to specify the client "SHOULD" do the translation?
• If it is necessary to specify, then shouldn't we say "MUST"?
  • Is there a case where the client should not perform the translation but will still display the timestamps to the user in local time?

Issue done.