Gary, you're not quite getting it. I just did a 7-day trip on the Teton Crest in Wyoming, mostly off trail. Not sure how it compares to the WCT, but it certainly wasn't any walk in the park (well, we were in National parks part of the time, but I digress....). And we certainly had to 'carry it all' with us. My pack started somewhere between 25-30 pounds including food and water (not sure because I didn't weigh it after I left the house and took my share of group food and gear). And I had some stuff I didn't need (had never hiked in Wyoming or thereabouts before and was prepared for about any weather - we only had sunshine!). Our 'guide' probably was carrying around 25-30 pounds too, and he had the Sat phone and a few other incidentals. And, of course, generally the packs got lighter after each group meal was consumed (two per day).
50-55 pounds is way heavy by the standards of most BPL readers. Your pack doesn't have to be that heavy if you only stop thinking like the 'traditional' backpacker, guide or not. Because if you think 50-55 pounds is an acceptable weight for a week, not too many people on this site are interested in letting you take them anywhere....