You're right. If you have many page views, you may want to use a workspace that actually closes views when they are not visible.
The thread referenced by Dan contains some useful information.
See also my response to your other post:
It seems to me that the base PageController class should be fielding the SmartPartClosing event from the workspace and terminating itself. Next week I'll ask Ward if it's intentionally omitted or just an oversight.
Hope this helps.
Bill Jensen