If you know surviellance is running a skills check on someone at your table, this is the time for you to hit 12 vs. 4, or to double for way less with 12 vs. 2 or 3, or to hit 13 vs. 2, or to double 10 vs. 10, or to split 2/2 or 3/3 or 7/7 vs. 8, or to split 9/9 vs. Ace, or to Insure any hand for...