it is with adding a new user and removing a user, the delay is in minutes so your idea wont work
The help files do mention that ruser will be delayed while mIRC does a lookup.
Note: The /guser and /ruser commands do a /userhost on a nick to find the nick's address, thus they are delayed commands since they need to wait for a reply from the server. mIRC tries to get around this delay by maintaining it's own Internal Address List which will speed things up in certain situations.
