Is there a bug in the "total reputation" tab?
There is a "5k total rep" vs 56 shown for a username.
The "total reputation" number will only ever match the user's reputation to the right if they have not referred any users to the proposal. The number is actually a calculation of that user's reputation and all the reputation of every user they referred to the proposal.
Why does that extra number exist? I have no idea. But that's the way it's always worked.
Not convinced. I have seen several cases now where when you drill into a user you can see many thousands of rep across the networks but the total rep can appear as just the rep on area51 for some reason and this is when no users have been referred by them. It just means you need more than the 100 people with a score of 200 or more which is a little frustrating.
For example: https://area51.stackexchange.com/proposals/126136 Alexander Theißen
Edit: After a while this seems to correct itself so I am guessing there is a scheduled process somewhere...