Diver knives.....

Years ago I learned the hard way why you wear them.
After a swift water rescue I was retrieving the canoe
By myself, the rest of the team took off with the people to meet the helo
In the process my shoe laces got tangled in some bushes, in chest deep very swift water.
Took me over an hour to free myself
Thought I was gonna drown
After that, hard bottomed diver shoes and a sharp, sharp diver knife