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I think when people engage in the kind of disruption your example shows, they can't expect privacy, especially when they're repeatedly revealing their own IP addresses.
How did they reveal their IP addresses? Editing not signed in and then someone doing a checkuser against the IP address. This seems to contradict:
Your IP address will no longer be visible to other users, meaning you will have greater privacy. (Your IP address is still saved and accessible to users with Checkuser permission, but it is rare for this to be used.)
It is not that I get that excited about IP addresses myself, it just seems to get Wikipedians frothing - and we are told that the magic of signing in is that we do not have our IP revealed - unless it suits Wikipedia admins that is.