I thought I was pretty familiar with all of the CCI material on this kind of topic but I missed this one. I think it sounds interesting and might warrant some experimentation but I am not sure of the advantage of using PE to adhere it over say using a 3M spray adhesive (I forget which number right now) that - once cured - passes Oddy tests (not sure that this matters since it is behind the barrier anyway) which is an old timey solution.
The 3M solution is faster but I guess the PE solution is cheaper and less messy/stinky.
It seems to me that they both share the same intrinsic weakness though - using foil without a barrier on the outside leaves it vulnerable to pinholes if it is not handled pretty carefully.