Maybe he soft proofs from the beginning because he always prints the same way on the same type paper and same printer. So for him that works.
This still seems nonsensical to me.
What about output to the web or other electronic device?
Softproofing is not just about printing.
Much better to do what Jeff Schewe suggests: create a master image and then create softproofs from there for whatever output is required. It is very useful to softproof while comparing the master and the softproof copy - that is how one gets the softproof as close to the master as possible - and by extension the print or the electronic display version.
Tony Jay