You don't point them all to one wallet (well, you kind of do, but not really).
You would have your bitcoin miners query the bitcoind daemon on the server computer (which can be any of the miners, to make that clear), and thus only the wallet that that computer uses will get the generated transactions. It's much less work.
With copying the wallet, eventually they would desync as the keypool was used up and they started generating new addresses for themselves. Additionally you have to have a full install of bitcoin on each computer, whereas you only need the miners and one central client in my suggestion.
I see where you're coming from! Thank you very much! So I just use RPC or w/e to connect all the clients to my one central server. I'll definately do that thanks!
P.S. According to http://www.alloscomp.com/bitcoin/calculator.php
in 6 days, 5 hours, 35 minutes there's a 95% chance I'll generate my first block and collect my first 50 bitcoins. Really!? That short amount of time I earn about $150 USD? Why shouldn't I invest in a large network of computers and make a living off of bitcoin?