UFS journal size

[Ross]

Quoting the manpage:

         -s jsize  Specifies size of the journal if only one provider is
                       used for both data and journal.  The default is one
                       gigabyte.  Size should be chosen based on provider's
                       load, and not on its size; recommended minimum is twice
                       the size of the physical memory installed.  It is not
                       recommended to use gjournal for small file systems
                       (e.g.: only few gigabytes big).

My question is: if I have 4 or 8 GB of RAM should I create 8 or even
16 GB journals?.. This seems huge especially if the fs size without
journal is only 10 gigs. Or the recommended minimum is for systems low
on RAM?