I suspect it will empty out too quickly with the opening as big as an open bottle top (inverted so that it's open at the bottom). Others have done this technique but with a smaller hole opening. Unfortunately, bottle shapes aren't designed to keep the orientation in one direction, but a flanged shape with air on top could work as could something with a low density (e.g. foam) top.
I believe the use for this would be more for vacations when one is not around to dose with chlorine, though for up to a week the use of Trichlor pucks wouldn't be a problem unless one's CYA was already too high.