When SELECT meets certain criteria, Foxpro does not really create a new cursor,
but rather it simulates a cursor by merely applying a filter to the input table
with a new alias name. These criteria generally are:
(1) query based on a single table;
(2) query contains no calculated fields; and
(3) query is fully Rushmore optimisable.

Ultimately, however, as I have told people who called on the product support
line, you can never take for granted that this will happen ALL THE TIME.

The only way to insure you get a real new cursor is to include the NOFILTER clause.