unique permalink for huge gain of time

i would like that every post has a permalink that is independent from the category or thread it's in

as many companies we change our categories and thread regularly, some stuff go in archive,

for exemple we have a question thread - an answer thread - an archived questions thread

when we change a post from the thread "question" to move itto "archive", its permalink is not working anymore

This makes all the old links obsolete and they have to be changed all the time

same stuff when we rename our threads, the posts permalinks dont work anymore

when we change the title of the post also