I've seen players refused induction for a LONG time for it (sometimes permanently). It's very common for them to be refused promotion and leader spots (that they otherwise would have gotten), even after going through a "redemption arc". And certain Imms have absolutely made it a habit of coming down and forcing a redemption arc (or extending it, if the player has already addressed it IC). That's the practice I'd like to see go away, in most cases.

In my opinion, it doesn't matter how often #3 happens. It's someone elses actions.. that's on them, not on you. You shouldn't be held responsible for someone else's evil decisions. Your actions? Absolutely.
As far as #2, I agree with you. If you keep making the same mistake, it's not a mistake anymore.