MySQL：Subquery vs. Join 效能何者為佳？

在網路上查了一些資料，似乎尚無定見

但是：

MySQL官方說：「A LEFT [OUTER] JOIN can be faster than an equivalent subquery because the server might be able to optimize it better — a fact that is not specific to MySQL Server alone.」
http://dev.mysql.com/doc/refman/5.1/en/rewriting-subqueries.html

但是有些文章說 subquery比join好？
http://qops.blogspot.com/2008/01/inner-join-sql.htm