There problem we do have is much much smaller, and relates more to incivility and NPA than to the banning policy. It involves not seriously believing people to BE a banned user, but sort of loosely tossing around the accusations of a vague sort of link to banned users. "Supporting" the banned user. "Agreeing with" the banned user. "Friends with" the banned user. "Your buddy" the banned user.
Such statements often have a bit more behind them than the people who make them are at liberty to disclose openly.
Oh Lordy, Durova-- that's true, there are cases like that but it's an incredibly dangerous direction. Secret claims the accused person can't rebut. Secret claims that can't be discussed in public. And as you imply, "doube secret" evidence-- where not only is the specific content of the evidence secret, but even the existence of such evidence might be secret (or at least unknown). ******* More than 90% of the material I draw upon is already public information for anyone on the planet who has an Internet connection and the smarts to find it. Nobody took me by the hand and showed me how to parse it. Nobody delivers it to me on a silver platter.
Delving through that material takes hard work, and the fruits of that labor have stood up to repeated scrutiny from the Committee and from numerous senior editors who hold a variety of Wikipedian philosophies. It would take a vast conspiracy to cover up the situation, if the problems I identified weren't actually valid.
To the maximum extent feasible I actually do share that evidence. If my intent had been to pursue some Star Chamber miscarriage of justice you wouldn't even know I had a hand in the Alkivar case and I certainly wouldn't have circulated the bulk of my evidence to nearly every Wikipedian who requested it. I am probably freer with this material than I ought to be.
It makes a mockery of WP:AGF to disregard the track records of both parties and presume such statements are baseless until proven valid in full view of sockpuppeteers who would then exploit the information to become better sockpuppeteers.
Armchair theorizing is quick, easy, and pleasant; actual gumshoe work is slow, difficult, and painful. Walk a few miles in those moccasins.
-Durova