Okay, I have 2 Burton shorty leashes, the 6 inch kind that strap binding to boot.
And I bought a long 2-3 footer, attaches to upper calf and then to binding.
Not one liftie or mountain worker has yet to ask or inspect a leash on my board.
I can see how it may help at the bottom of the hill, while you "strapping up", if there is bit of slope.
ON the Other Hand, I think I like the long leash best--for this use.
At multiple resorts (while walking to the gondola or the base of hill), I have used the long leash like a dog leash. Put your board flat on the snow, pull it behind you like a wagon No carrying needed.
My skiier friends look at me in disbelief, as the lug their heavy skis and poles over the shoulders.
Let's hear some opinions.