Originally Posted by
tfar
By all means, GF. Two 14 pound bags are a lot easier than one 28 pound bag, no matter what type of bag it is.
In your case you had a triple advantage:
1. None of the bags were at the 10% limit (or so I figure
), which makes it less stressful to carry any one of them.
2. Both bags were equal weight which is good for a balanced load.
3. One of the bags was a backpack. Even if a backpack is worn just with one shoulder strap, its weight is already shifted to your back which makes bigger loads easier to carry.
What I am talking about is a rule that makes it easy to determine whether a ONE (1) bag set-up with a SHOULDER bag is feasible.
You are a very smart and proficient packer. And still you were lugging 28lbs. Imagine you'd have had to carry that in a single shoulder bag. Is it possible? Yes. Will you regret it? Most likely! 
If you use a Skytrain, Tristar, Motherlode, Aeronaut or other convertible bag in true backpack mode, you will of course be able to put in even a 30 pound load - possibly more but then we aren't really talking about packing light anymore.
The Aeronaut due to its squarish main compartment is also not ideal for packing a suit jacket so many professional travelers need.
Till
Yes, I understand and agree. I was really offering an alternative to one bag. And I have taken a roughly 28 pound one bag (B&R 235x I believe) and I was in pain for a couple weeks afterwards from the stress. A Tristar or Skytrain would have been better due to the shoulder carry.
As mentioned above also, another advantage of two bags, other than carrying more, is that if one of them is a messenger bag or backpack with the tech gear it can serve as a day bag at the meeting you are attending. In the case of both of these trips I did that. For different reasons on both of these trips I didnt think I could do with only an iPad, so I also took a Mac Book air. That, plus the charger for it and the weight of the second bag probably was about 5 pounds. When I do travel with one bag, I try to get it to 18-20 pounds, which works for me. And as you said, that is often for non-work trips. But I do think that 2x14 lbs is as comfortable to carry as 1x20 lbs.