This is not all that different in method. Yes while it might not be the method they used for the
old glass bottles, the method is the same idea in principle, just meant to work with plastic bottles
and with a thinner design, which I have seen before. As the directions state, many bottles will
work but you will have to be extra careful in handling.
The principle is sound and
tested, practice will be required to get it down on standard coke bottles. The gimmicks are
accurate,