Originally Posted by
Tjaardbreeuwer
Two very different designs going on there:
some hybrids have the WPB in the lower legs, some have it on the knees and front of thighs.
I think the idea for the first design is that your lower legs might be in the snow.
So, you get the range of motion and breathability of a mostly softshell pant, but without soaking your lower legs, which aren’t as sweaty anyway. The clue is in the Trailbreaker name of the OR version. @concierge described this.
The idea for the second one is that you get more wind and precip protection where you need it, and more stretch and breatheabilty than full WPB pants would offer.
After all, you don’t get uniformly cold or wet everywhere on your legs when it’s windy or precipitating.
Some softshells (I know some from mammut) also address this by using thicker softshell fabric on the knees and front of the thighs.
Of course, the fact that both of these competing designs exist shows that there is something to be said for full WPB.
I think there is definitely something to be said for softshell on the butt, for range of motion. You also don’t get much precip hitting there because of forward movement and the protection from a backpack.
The same ROM thing could be said for the knees, except that they are very exposed to wet precip, and also knees get cold easily and don’t like it.
Vanity plays into this too. Most people, find preshaped, roomy knees a bit more acceptable than a saggy butt on their pants, so WPB fabric knees are not as much of a down side as WPB butt.
I don’t currently own any hybrid pants, because I need a rare size (32x36), but in general , I’m fan of hybrid garments, mapping each fabric to where it’s strengths are maximized and its downsides minimized. Like front and rear tires on a mtb.