Go pull out $15,000 in cash from your savings and attempt to go through some significant airport. If the TSA guy does some bag check...just watch the events that unfold and how quick they want to drag you into a room to interrogate you, and attempt to confiscate the cash. Watch the same event with $9,900 and how they let you slide by.
There would still be plenty of attention. LEOs are aware of smurfing.