Well I think BKF does re-passivate. I cut the handle and 'ears' off a stainless steel strainer (that sits in a pot) and it is now my hop-stopper. I cut them off with a dremel, scrubbed it with BKF, waited 10 minutes then washed it off, put it in the pot and did a 60 minute boil. I didn't see any rust in post-cleaning.
It should also be noted that I used a grinding disk on a dremel, not a saw. The saw might leave regular steel in the cut and promote rusting of the stainless.
"People should not be afraid of their governments. Governments should be afraid of their people." - V
Secondary: Shady Lord RIS, Water to Barleywine, Pumpkin wine, burnt mead
Kegged: Crappy infected mild
Bottles: Apfelwein, 999 Barleywine, Oatmeal Stout, Robust Porter, Robust smoked porter, Simcoe Smash