Thank you for the comment on multiline comments.
It is a stylistic point as to whether C-style multiline comments are a good or bad idea. Looking at their use in C shows that many times there is still a leading "*" to mark the line.
The working group does not intend to add multiline comments to SPARQL at this time.
We would be grateful if you would acknowledge that your comment has been answered by sending a reply to this mailing list.
Andy On behalf of SPARQL-WG