Very, very seldom have I ever heard of any movement.
Personally, I have NEVER experienced any dimensional instability.
I believe they want the wood at about 8% moisture.
I get my wood, cut it up into over-sized blocks, seal the ends in melted parafin, and put them on a rack up in the open rafters of my garage for at least 6 months.
The only things I do not stabilize are Blackwood, Ironwood, Ebony. I'll use raw curly maple, but then it gets an extended finishing process.
That stabilizing process impregnates the wood right down to the cellular level of the wood filaments basically turning it into a piece of plastic.
I can't recommend it more.
And the only way it gets done correctly is with the high tech process they have.
And, it's cheap! When all is considered.