Total Server Memory vs. Target Server Memory

Contrary to my believe that for a good SQL Server run the two should be equal, in the last couple of days I found two articles that advice that Total Server Memory should be less then Target Server Memory

http://download.microsoft.com/downl...31282b04d/Performance_Tuning_Waits_Queues.doc

"If Total Server Memory is well below Target Server Memory at steady state, it tells you that the server is not experiencing memory pressure."

h71028.www7.hp.com/ERC/downloads/4AA0-2948ENW.pdf

"Total Server Memory < 80 percent Target Server Memory "

Is that right? If you think yes, why?

Best Regards

Tom made a reasonable & true statement
but he is not saying what the value should be

the HP paper is of questionable technical competence

in any case, do not try to over interpret what counter values should be
the real metrics are
1. is your server having performance problems
2. could performance be improved
etc

a simple counter value does not answer the important question