I originally posted this link because I have an immense amount of respect for Mr. McHale, both for his outdoor accomplishments and the packs he has designed over the years. And I think it's always interesting to get another perspective on gear.
However, I do find myself disagreeing with his conclusion that UL packs are by necessity uncomfortable. I agree that once you reach a certain weight, 25-30 pounds and over, frameless packs will be uncomfortable for many people, but not all of them. I've talked to too many experienced hikers who have thru-hiked with frameless packs and really enjoyed their trip. I've logged over a thousand miles with frameless packs and definitely think they have a place for certain trips, though I admit, I would not use one for a thru-hike.
For me, my pack is the most intensely personal piece of gear I carry. Even if everybody else in the world loves a pack, that doesn't mean I will. I've tried to eliminate excess gear and own only what I take with me for most trips, but backpacks is where I make an exception. I own several backpacks for several different types of trips. No backpack is the best option for every trip, so understanding what gear you will need, the duration of your trip, and how much food/water you will carry is vital to selecting the right pack for the trip.
If I was doing a winter trip with sub-zero temps, I would definitely carry a more heavy-duty pack capable of comfortably carrying all necessary gear. Ditto if I was doing a hardcore mountaineering trip involving climbs. But most of my trips are in 3-season conditions with a BPW of 7-8 pounds, so IMO, I have no need for a bulletproof McHale pack. For extended trips around 3-10 days, I now use a custom-built Xpac pack weighing ~30 ounces and have had fantastic results with it. For me, this is a perfect blend of weight savings, and having a comfortable framed pack that supports whatever load I decide to carry.
That's what experimentation and experience is all about ... self-discovery and knowing what works for you.