"I can't see how the silnylon can mist"

It can.
I only have had that on a few occasions and I have been under pretty heavy rain many times.
If the raindrops are large enough (generally larger means faster) some will penetrate.
However that is one drop every so often, not enough to keep me awake.
(somewhat similar to the spray you get under an umbrella in similar conditions)
I think that some of the reports depend on how we interpret certain occurrences.
For example to one a few sprays is nothing, to others it is a deluge.
Epic (hilight) is much less waterproof.
Franco