You spend all day in the rain, or worse, crashing wet brush, you are going to get soaked to the bone in breathable gear. Doesn't matter how good.
In the snow, non-breathable gear bites.
Neither is the answer alone.
Here's the thing though: who's going to carry 2 jackets on a given excursion? I'm sure as heck not. In the conditions in which GoreTex will leave you soaked, a nonbreathable garment will leave you just as soaked. But in other conditions the GoreTex works great while the nonbreathable item... still leaves you soaked. I say the GoreTex (or whatever WP/B) is vastly more versatile for the weight and volume it costs me.
WARNING: Several climbers have blamed the waterproof/breathable fabrics for their close calls. They claim that no version of it can take the punishment of a storm on the walls.
You have to take into account that this essay was written in the early to mid 1980's. I know, because it was in the Yosemite guidebook I had in 1988. WP/B technology has advanced by leaps and bounds since then; see Doug's notable info on GoreTex survival suits. However, it is true that YOSAR might still fine you if you get rescued in a storm using down sleeping bags.
Here are a couple of personal data points that are not statistically significant:
- I have been using a Lowe Alpine WP/B anorak (13 oz in size XL) for about 8 years in conditions ranging from 3-day nonstop downpours to subfreezing windstorms. Through it all it has never leaked. Even when the outer nylon fabric soaked through, I did not get the "trash bag effect" and was only mildly steamy inside. In those conditions it dries in minutes when worn near the fire.
- Over the same time period I've been using a pair of Marmot PreCip pants (8 oz in size XL) in the same conditions as the Lowe anorak with similar results.
Miracle garments or blind luck on my part? I dunno, they just work.