Just an aside:

When ever the strike indicator subject comes up
I'm always tempted (and I seldom resist temptation)
to say "why not use a foam dry fly as the indicator instead,
the fly catches fish and the yarn indicator doesn't."

Invariably, someone else says "because you can't move
the foam fly up and down the leader, so it's not as 'depth'
versitile"

But it's worth pointing out that isn't entirely true.
I sometimes put a foam hopper way up the leader,
so it attaches to 20lb test, for instance, in order to
make an extra-long dropper, for extra depth.

The foam hopper indicator still works, and fish still
bite it. It may not move as quickly or conveniently,
but you can put it at (almost) any leader position you want.
And it still does catch fish, which yarn will never do.