From a simple breath test, I could quite easily tell the difference in breathability between the old Houdini and several garments made from Pertex Quantum. Pertex Quantum was VERY noticably less breathable (though still slightly breathable - 1cc sounds about right). This was also true for other Pertex fabrics, such as Microlight.
I do prefer Pertex Quantum and similarly less breathable windshirts for climbing and other more 'static' activities, such as canyoneering. I wonder if this could be responsible for the change in Houdini fabric - most of their sponsored athletes are climbers, not hikers/backpackers.
I breath-tested about 15 windshirts last fall and found that only the old Patagonia Houdini and the Stoic Wraith had breathability suitable for backpacking and hiking. It's unfortunate that both garments are now discontinued, so to speak. It's a major disappointment and I intend to baby my Stoic Wraith from here on out.
If I recall correctly, using the breath test, I found MLD's fabric that they use on their quilts to be more breathable than Pertex Quantum. I don't believe it is as breathable as the old Houdini, but I can't say for sure. Perhaps MLD could step up, here?
I found that none of the 7D or 8D fabrics were that breathable - similar to Pertex Quantum or worse. The fabric used in the Stoic Wraith was the only exception. I have NOT tried Nobul1, which MAY be more breathable - I've read about it's lack of downproofness, which would indicate to me, that the material is either less tightly-woven than others, or less of a cirre finish.
As for the breath test, I've found it to be very accurate. If you can "easily" breath through the fabric, but feel strong resistance, that's the one you want. If you can barely breath through the fabric (almost feels like you're going to hyperventilate), it's going to be only mediocre for activities such as backcountry skiing, biking, hiking or backpacking.
I'd like to test out some biking windshirts, as they might fair better, but I'm happy with my Wraith and biking windshirts don't have hoods, so I haven't bothered yet.