pg_dump and --inserts / --column-inserts

Hi,

the explanation of the --inserts option of pg_dumps states that

"The --column-inserts option is safe against column order changes, though even slower."

The way I read this is, that
   INSERT INTO table (column, ...) VALUES ...
is slower than
   INSERT INTO table VALUES ...

Is that really true?
Why would explicitely stating the columns be slower than relying on implicit column ordering?


Regards
Thomas