PS. It will also make it a lot more visible! The refractive index
depends on an unmarred surface! Which is another reason the
"invisibility" is more or less useless, and basically just a marketing
gag. Glinting line will spook a lot of fish, and if you canīt de-glint
it is practically useless. It is to me any way!
PPS I donīt use many flies smaller than a #16, so the line is
actually of very little use to me, except for a couple of special
tactics, one of which is fishing weighted flies deep on fine tippet.
The finer the tippet, the faster and deeper the fly sinks.