I only used SilkTest briefly a few years ago and I don't have a test system at the moment. So I can't give any detailed advice.
But some googling convinced me that the answer is: yes, this is possible.
SilkTest and SilkPerformer (from which the TM ART Monitor Workbench is derived) have highly active forums that are searchable by normal search engines.
The basic approach would be to use a "for" loop and a sleep in your SilkTest testcase.
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