Some problems already have been solved!!..Like the very low cost...very low Tec ...VERY reliable...easily and quickly tested ...very durable...and well proven Kill-cord IMO..
If your the type to forget to clip it on ...you're also probably the type to forget the wrist band....if you can discount electronics and over complicated Tec (especially when there's no need in the first place!) in the Salty Marine environment it is always a good idea...so why add to it?
I also like the fact (with the extremely well tested Bog standard Killcord) the engine cuts LONG BEFORE you're ACTULLY outta the Boat too!
If it ain't broken....