This is not correct. DRM manages copypools identified using the SET DRMCOPYSTGPOOL command. Consider my configuration:
tsm: TSMSRV1>select STGPOOL_NAME,POOLTYPE,DEVCLASS from stgpools
STGPOOL_NAME POOLTYPE DEVCLASS
------------------ ------------------ ------------------
COPYPOOL COPY 3590TAPE
DISKDIRPOOL PRIMARY DISK
DISKPOOL PRIMARY DISK
ONSITE_COPY_POOL COPY 3590TAPE
TAPEPOOL PRIMARY 3590TAPE
tsm: TSMSRV1>select * from DRMCSTGPOOLS
STGPOOL_NAME
------------------
COPYPOOL
The tapes in the copy stgpool COPYPOOL are managed by DRM, however the tapes in the copy stgpool ONSITE_COPY_POOL are managed by DRM. I use ONSITE_COPY_POOL to backup DISKDIRPOOL to tape and still be able to have that backup on-site. I also backup DISKDIRPOOL to COPYPOOL, but that backup goes to the vault.
<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font class="pn-sub">Quote:</font><HR></TD></TR><TR><TD><FONT class="pn-sub"><BLOCKQUOTE>As long as you define whatever pool you don't want to go to vault as a primary sequential storage pool, it will never be included in your DRM offsite media, but if you make it a copypool, DRM will always want to send them offsite.</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE>[*]null