Question about expung claimlist

Hello,

Can anybody tell me exactly what the Expunge Claimlist command does?

From what I understood its only purpose was to release claims that were kept locked and the user exited the software in an abnormally way, like a crash.

But recently I saw some people refusing to use it because it would mess with the extract claims as well, releasing all elements claimed by EXTRACT CLAIM in the extract databases.

Thanks in advance!