I just got back from a Sierra 4-nighter (planned as a 5-nighter) in the Hoover and Emigrant Wildernesses with two old backpacking buddies. I'm the only lightweight backpacker in the group. (I think lightweight backpacking should just be called "backpacking", and traditional backpacking should be called "heavyweight backpacking", so we don't seem like crackpots, and they do.)
I had some community gear that I wouldn't normally select, so my base weight was a little heavier than usual, at around 12 lbs. I also brought too much food, and couldn't find my slightly larger backpack, so I only barely managed to cram everything into my Gossamer Gear Murmur. At the start of the trip, with probably just over 20 lbs, it was a little too much to comfortably carry without a waist strap, but I was probably more comfortable than anyone else.
One friend, who we'll call "A", is up on gear and brings the latest and sometimes lightest that REI has to offer, but lots of it. Loves lots of fancy kit. GPS, adjustable down pillow, etc. So his pack weight is probably twice mine. He worries about his feet and legs making it far, so he laces into big hiking boots and vetoes longer routes. Yet one day we made it far longer than planned and he kept up the whole way; I think he limits himself.
The other friend, "B", feels nostalgic about all his old gear, and also likes to be devil-may-care about bringing stuff. "The report called for a cold snap, so I just threw in my four-season two-person tent at 6+ lbs." That's fine - he can hump it all at as fast a pace as I can, but there isn't so much left in the tank at the end of a half day of travel. And he got blisters and became sometimes campbound, and slower at water crossings.
So I found myself alone in having excess energy and enthusiasm at the end of each half day of backpacking. I did a little day hiking, but I would have rather done so with my friends.
The mosquitoes were also horrible the first half of the trip - if we were all in the same boat we'd have kept going in the afternoon to find somewhere better to stop.
The trip was engineered, eventually, to get us closer to the exit sooner. No one else wanted to stick it out for the extra night, so we exited early. I blame heavyweight backpacking for this.
I was in just a bivy; not just to save weight but to commune a bit more with nature. My trail runners have the same benefit to me - rather than just freight-training over terrain, I light having to consider where I'm stepping; it's fun and makes me feel more in tune with where I am. Plus, *I* didn't get any blisters.
But I don't think I showed anyone the "light". They saw the bivy as discomfort, and the shoes as an unattainable convenience. At least B liked the Steripen.
For my part, I never managed to exhaust myself; the mix of styles in the group kind of spoiled that for me. Also, my comfort with less kit, plus the extended potential range that results from a light pack make the wilderness smaller. Instead of feeling really out in the boonies, I knew that at any time I could throw on my pack and hike out in one of several directions without much trouble. In a sense that lessens the adventure and charm of backpacking, which used to seem more exciting when I felt more intimidated.
So that was my experience, and will be again. My mom is the only person I know who values the lightweight philosophy. I've really got to get a trip in with her!