I knew I wasn't alone. Btw the areo-foils on my leash are the drag co-efficient of 66^10 at a water temp of 456 Kelvin, just in case you have super duper physics chops like me. I know all about math, sciences and other things rich folks think about while they don't have to work.
Leash?? Are you guys kooks or what?? Only morons use a leash. I go totally totally leash less........
Think of your leg rope as a seatbelt for your surfboard. If you don't wear it - you go through the windshield.
Working with line a lot, I find that cold water has little effect on knot durability. Warm water makes line far more pliable but not notably stronger. However, if you’re surfing when it is wicked cold, like below freezing cold- that could somewhat affect the knots holding power. You leash line already has a 40% or more reduction in strength from a knot being tied into it. When you’re surfing in water that is freezing, it is possible for the water to freeze inside the line fibers, make them brittle a then there is a possibility of snapping. However, that is more noticeable in line that doesn’t move for a long period of time. Leash line moves quite a bit so that shouldn’t be a problem. It may be a problem if you keep your board outside but not many of us do that. The bigger, more notable enemy of leash line is salt water. Constant exposure to the salt environment dry rots nylon line really bad. When you combine salt exposure and sun exposure it is a double whammy. Most of us don’t rinse our leash line thoroughly so that increases the risk of breakage. What happens is you surf a lot in summer and then when it finally gets big—a.k.a. winter, the line is already worn out and then snaps from the bigger waves. A lot of times knot failure on leash line is simply a poorly tied knot. I like to leave ¾-1” of a pigtail on the backside of my knot to give me leverage to tighten it up. I use a standard overhand knot, looped through itself inside the plug. Just my opinion,