I'm breaking this thread because a) it is always possible that there are unique factors in play in the ru.wikibooks situation, and b) this is a wider issue in any case.
Here is my opinion:
*No policy, however good or golden, should ever override human judgment.* This is true on every level, on every project. Policies that suggest otherwise *should* of course be rewritten; but in any case, they *must* be ignored.
It should go without saying that blatantly abusive behavior by the lone admin on a project without a strong local community calls for direct and immediate corrective action, regardless of policy.
If the people who are charged by the WMF community with project stewardship do not feel that their own judgment is good enough to handle serious problems in a moment of crisis, then that is a very serious problem which threatens the WMF's entire model of governance.
Cheers,
Sam