>We often use macro substitution in the definition of views to make the "where" clause dynamic. Is that a poor use ?

Actually the "where" clause and other places in a SQL SELECT are the one exception to this rule. (I should have mentioned this in my message to Renoir.)

Because VFP takes the SQL command and passes it off to a SQL processor the macro is substituted before it is passed off and the performance hit is negligible. In earlier versions of VFP you could only use macro substitution. I'm still learning where things have changed because the differences are subtle.