Journalling *FLDBDY

I was reading the help on *FLDBDY:
Journaled files may have journal entries deposited with
minimized entry specific data. The minimizing for journaled
files will occur on field boundaries. Therefore, the entry
specific data will be viewable and may be used for auditing
purposes.

"May have" implies "or may not have".

For example, I have a journal set up this way. Then I created a table and
associated it with that journal.
CREATE TABLE ROUTINES/AUDITTEST
(MYKEY INT NOT NULL WITH DEFAULT,
MYRATE DEC ( 5, 2) NOT NULL WITH DEFAULT)

I inserted a few rows.
Then I changed one row.
UPDATE ROUTINES/AUDITTEST SET MYRATE=100.9 WHERE MYKEY=90562

My interpretation of *FLDBDY is that I should only see the contents of
MYRATE in the journal receiver. However, when I look at the receiver for
the update I am seeing:
Entry specific data
* . . . + . . . . 1
'000161C210090F'
(Ok, so many storing a field in binary makes it a little confusing.)
But basically both columns in the table are shown. Actually, this makes
it easier for auditing purposes. Like, I can tell the employee number of
the employee who just got a pay raise. But how does *FLDBDY save any
space?

Rob Berendt