It's really 10lbs. And I've addressed the weight as compared to minimal saddles on several occasions and from several perspectives.
For my style of hunting, it works rather well. I walk really long distances, oftentimes scouting most of the day, to set up for evening sit. I think I've made 3 sits on public land less than 1 mile from where I park my truck or bike. If I kill a deer, I have very little desire to leave and come back. If I'm filming, I currently have a cheapo 20.00 allen kid size backpack with the film gear in it. That's it, everything else straps on the hybrid. I'm very close to not needing even that little tiny pack. So for me, the weight difference versus the Kestrel is about 3lbs. Because if I'm using the kestrel, I'm toting in my MR Popup to carry my gear and potential kill. Honestly, I have a difficult time choosing between the two. I have a couple of spots that dictate one or the other, but both function well.
If I'm not packing deer out (I do hunt close on occasion, and some flat open ground, but it's rare), Much of the advantage of the hybrid goes away. However, It's significantly more comfortable than minimal saddles. And it is slightly easier to maneuver and shoot out of than the web. But the disadvantage of the weight disappears when your close - It doesn't really matter.
Another big advantage to me with the hybrid is a platform becomes purely a luxury. You have hardly any weight on your feet unless you stand/lean to shoot. I'm personally comfortable on ring of steps even in kestrel but some guys require more comfort of a platform. That goes away with the hybrid-along with the weight - which is what this post is about.
Fact of the matter is, the weight difference, when taken into context of many hunting scenarios, is negligible or irrelevant. There are some that it makes less sense than other options. But I'm finding those fewer and farther between the more I consider it and spend time hunting with the hybrid.