Sounds like I'd get a camera out on this one. If you're torquing the string you'll see it with the camera above and behind you. That arrow will be bent at full draw.
Its hard to say much about a test medium of every once in awhile it will group with the bow vertical. Whats it doing the other 70% of the time when they dont group?
Personally I pay little attention to how much I cant when bareshafting. I'm close, 5 or so steps from a target. My bow is typically canted when I stand in my ho hum wanna be a good shot position at 15 or so degrees, at that close of a range that little angle is going to have very little affect. I've also bareshafted at one point out to 40 yards when I could actually hit the ground without it impaling itself on my arrow. I shot the same, still slightly canted and wamo.
if I was having these issues, here's what I do....start bareshafting first before I messed with group testing or anything else! Figure out if you're weak or stiff and start making the nessicary moves to get close. It will get you closer to where you need to be faster and THAN start group testing. Basically it will show you weak or stiff immediatly without having to shoot a pile of groups. I consider group testing more of a fine tuning method, and bareshafting the meat and potatoes of getting to that fine tuning point. I love to shoot, though I'm doing it less and less. This kind of shooting can become frustrating and leads to other issues like adhd, ocd, and bowaholicism. Their is a support group for each which will do little to curb the issues lol. Ok ok, it's been a long week of night shift work without pay, I'm loosing my mind hehe.
All joking aside: It could be you, form problems, it could be tuning, it honestly could be a LOT of things. Start ruling out knowns before moving on, elimating issues one at a time.