Remove weasel word.

SHOULD or SHOULD NOT. There is no attempt.

doc/draft-ietf-codec-oggopus.xml

@@ -1170,9 +1170,9 @@ Making this check before allocating the associated memory to contain the data
 Immediately following the user comment list, the comment header MAY
  contain zero-padding or other binary data which is not specified here.
 If the least-significant bit of the first byte of this data is 1, then editors
- SHOULD attempt to preserve the contents of this data when updating the tags,
- but if this bit is 0, all such data MAY be treated as padding, and truncated
- or discarded as desired.
+ SHOULD preserve the contents of this data when updating the tags, but if this
+ bit is 0, all such data MAY be treated as padding, and truncated or discarded
+ as desired.
 </t>
 
 <section anchor="comment_format" title="Tag Definitions">