A common idiom that arises is that a thread knows Inv is stable because he owns some unclaimable object o. Unfortunately, he can't form a claim of this property directly, because the claim would be invalidated when he unwraps o. The solution today requires making another, claimable object that owns o, transfering ownership to the new object, and constructing the claim owning it. Moreover, to open o, he has to first destroy the temporary claim and unwrap the temporary object before unwrapping o. All this is a mess.
If we exposed version numbers and their the monotonicity, all of this can go away; we can just form a claim that claims
o->\version >= \when_claimed(o->\version)
&& (o->\version == \when_claimed(o->\version) ==> o->\closed && Inv)
Now, he can use the claim as long as he knows o's version hasn't changed, and he never even has to bother destroying the claim. Nice.