Even if the block later turns out to be a mistake, or just very short, it will leave traces on that user's perception of Wikipedia. See Prahlad Balaji for an example of the latter.
On how to bait CheckUsers: see here.
But here is another malicious way to bait a CheckUser:
Embarrassing user names!
As we know, user names of sock accounts are publicly exposed. Some of those user names are quite funny.
However, this list of sock accounts can be misused by a sock baiter to have embarrassing names.
If you are on a network with the target Wikipedian, you could choose very embarrassing user names, and these public CheckUser categories will make it appear as if your target has created these accounts.
And if your target user tries to dispute the account belongs to him, he will quickly lose talk page access because trolling.
Example key words for embarrassing and offensive user names: (add numbers if used)
I am not encouraging anyone to actually do it, just exposing how easily their CheckUser system can be abused by baiters.
- Virgin at 25
- tiny d1ck
- [some political statements]
- I love Katja Krasavice [or other name]
- I smoke crack [or other drug]
- Fat pride 2020 [or variant of it]
- Natalie Hage is hot.
- I cheat on my Girlfriend
Their CheckUser system is not just bogus. It is a bug.
I am sure people have already been engaging in baiting with embarrassing user names.