Another example is when you 16 main racket that skips 7&9T and your mains tie off at 6T. Now you going to have two strings blocking 7T. Put the awl in before you run the 7th main run one string under the awl and the other over. When you're ready to tie off slide the handle back insert the tail to be tied off and remove the awl.
In this situation you will have a blocked hole (7T) on each side of the racket so a second pathfinder awl will be useful. For those of you that have one and don't want it let me know.
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