Comment on Dropping and creating tables in read only tablespaces?! by Praveen N

Thanks for the post .
I have a question about sharing tablespaces using transportable TS :-
I share same read-only tablespace (same data files) between two different databases . When I drop a table from one database I can see the temporary segments like you said , but the same object in the other database has no impact even though it shares the same datafiles and tablespace . how?