I don't really think there is a need for poly going around. Unless your having problems with tape sticking to the lace.. which I don't.. or you are using a liquid adhesive and find it easier to clean glue from poly than lace.. I don't see the point of it.

When people say tape is easier to attach and remove from poly.. take it with a grain of salt. Tape is just as easy for me to apply on lace as it is on poly.. and removal is much easier on lace. A lot of polys the tape is hard to get off, and a lot of times leaves a sticky residue on the skin that is tough to remove. Theres different types of poly. the thickest one is probably the easiest to work with, but if u get a thinner poly it can be really annoying to remove tapes. With lace all you do is squirt alcohol through the lace and it comes right off clean.