Yep, I`m basing on my personal experience also. When I quit compounds & first started shooting stickbows(15 years ago) I did not even concern myself with weight or spine, I was just concerned with hitting the bale at 5 yards. I found as I got better with my shooting, arrow weight & spine factored in more & more. I wanted to be as accurate as I could be.
For an example, take 6 spine matched arrows of varying weights, say 50 grains,& shoot them at 20 yards. You shoot 3 in the bullseye, 2 go 8" low & one is 4" high. Was it you or the arrows? You wont know, so in your mind you try & compensate on the next group & you are all over the place. I have had this happen to me & seen it numerous times. If the arrows are matched real close, you KNOW it`s you.The weight of the arrows is a non factor.Now you can work on the real problem, your shooting.
Take the top shooters with any weapon, selfbow, compound olympic recurve, rifle whatever. The best shooters will always match their projectiles as close as possible. If you took the 2 best stickbow shooters & one had matched arrows & the other had weights all over the place, who is going to be more accurate?
Some guys just want a reasonable degree of hunting accuracy, which is great. For them, it is not going to be a great concern. Some guys like me are nutty about the little stuff. There is a name for us, but it is not nice