I spray with water till damp. Roll it up and wait a few hours. Then tumble dry. Figure it probably shrinks somewhat but I don't know if it shrinks the entire 3% as claimed on the label.

I never do. I love the look of the quilt when it shrinks.

No,never

The only time i washed my batting was when i got a huge smudge of dirt on it, from it being on the ground

I like the scrunched look of an older quilt, so I wouldn't preshrink either batting or fabric.

However, I have a sister who uses 100% wool batting (her grandkids live in Alaska) ..I don't believe she has ever pre-shrunk, but then I'm not sure that she realizes that wool batting will shrink badly if washed. If I were to use wool batt, I surely would preshrink. It has occurred to me that I really should mention that to her, but she may know it.

I have never tried it, but I am always open to learning anything that would make my quilting life easier.

Never.. I wait until the quilt is done, then wash the whole thing.
But then, I seldom prewash my fabrics either.

I would never have thought to do that! I just take it out of the bag and use it.

I don't pre-shrink batting. I like how it scrunches up the top when it is washed. I like the crinkly look. I find it also helps hide a multitude of "quilting" sins when it is crinkled up. :)

I do try to spread it out and let it rest to get some of the creases out if it is from a bag.

no one i know does that
whats the point?