var/client_file = Import()
var/savefile/F = new(client_file) //open it as a savefile
F >> usr //read the player's mob
I was going to say that it should not return ..() since the client will already log into the loaded mob because of the F>>usr line, and ..() would make it call Login a second time (according to the client/New entry it should detect this newly loaded mob as having the same key and call Login for it), which would not be good.
So I went over to client/New entry and double-checked it to be sure and even ran a test. It appears that client/New default action checks to see if you are already logged into a mob and skips all the mob creation/logging stuff if you are already connected to a mob, but it does not say anything to that effect in the client/New entry in the reference.
This may seem insignificant, but as you can see it actually caused me to believe that some other code snippet was faulty when in fact it was not, so I thought it was worth mentioning.