Old thread, but I have a question I haven’t adequately answered yet. I am considering adding a Sherman to my Stryker. Primary purpose would be to hold 15x56 binos and perhaps my puffy glassing gloves. I want to be able to use it as a Grab-it for my tent as well. When not being used as a Grab-it, I want it snug, not floppy. How are you attaching the Sherman? Edit: I don’t have the Sherman yet so I can’t just experiment.
Interesting thought... I’ve got both but use them on different packs. I played with the mounting points to see if they line up - the inside tab on the bottom of the Sherman matches the bottom loops on the Stryker. Likewise, the top loop point on the Sherman also aligns with the upper attachment points. So - in theory - it will “work” on paper.
After looking at this, though, I think you’ll either wind up stacking straps (adding weight or making a clunky setup) or giving up some of your compression of the Stryker bag to the frame, which we need to keep it snug. Adding a Sherman to the outside of a bag that’s already the far side of a load sling could get a little cumbersome and Clampety. Thinking how much weight a set of 15x56 would put that far outboard, it’s hard to see how you will avoid sagging. But... I’m far from knowing everything so these are just a few thoughts. These bags invite imagination, though, so don’t let me dissuade you. Given the tinker factor that runs high with Kifaru users, I’m sure someone tried it and I’m as curious as you are to hear how it may (or not) have worked.
I carried my Stryker all season during archery in September and found it to be a fantastic day hunting bag out here in the west (Colorado). I resisted the urge to add pouches to the outside of the pack bag and, instead, use a medium and large belt pouch on the interior panel for my kill kit and game bags. That system worked really well for me and kept the outside of the bag slick, which helped keep me from getting snagged up when bushwhacking.
The pics show the attachment points and how I set up the belt pouches on the interior panel. And yep... I hit that Camofire deal yesterday and ordered a full set of Highlander pouches to build out my day hunting rig, because there can be only one...

(If anyone has a line on a bottle pocket in Highlander, hit me up in the PMs)