Wi-Fi on hardwired iMac? I have a small network consisting of a couple of iMacs hardwired to an AirPort router via CAT 5e cable, and a couple of iPhones. Since the iMacs are hardwired, I'd normally leave Wi-Fi turned off on those machines. However, I have found Wi-Fi to be useful for AirDrop between the iPhones and the iMacs, and for AirDrop between the two iMacs.

Here are my questions:


Is there any way to leave Wi-Fi on for the iMacs, but prevent them from using it to connect to the router? The AirPort is running WPA2, so I know I could simply omit the WPA2 password from the iMacs. Is there a better way?
Does it do any good, or any harm, to let the iMacs establish a wireless connection to the router, in addition to their wired connection? It occurred to me that the additional connection might boost throughput, if the router knows how to use it. Is that the case? 


Thanks for your help.
Without special software or hardware to do so, multiple connections are not combined for increased throughput, knowing as bonding. The connections are utilized in the order shown in System Preferences > Network (screenshot below). You can change the order by clicking the gear icon > Set Service Order.

There is no harm in letting the computer connect to the router, other than possibly a slight impact on load in the router - but assuming the connection is not being actively utilized, impact should be slight to none. The only way I am aware of to prevent the Mac from connecting to the router is to not tell it the password or turn Wi-Fi off.