Hey Jeff,
I can agree with you, cause I know we've got some code here at MEI that does this very sort of thing. I always tell my students, who are typically not well-versed in the whole private data session concept, that using this command is evil. This prevents them from trying to use the SET DATASSION command to solve problems that are better solved by knowing how data sessions work. Obviously, if you play with the Datasession property, you should know the consequences.
Obviously, you caught me being a little more strong with my words than I should have been - saying "never" is always wrong in this business. <g>
Regards,
-Chuck Urwiler, MCSD, MCDBA