Install armory 2 times in separate folders
Configure one to never have internet access and block it in firewall. Install private keys in this wallet. Use it to only sign a tx.
Open the other wallet which has internet access > import signed transaction > broadcast
Will this help a little from a security point of view? Seems to me that it will help with any bugs in the wallet software. Of course external factors like keyloggers are still going to be an issue...
Just curious. Not planning to do this.
You're describing an air-gapped setup, considered to be (one of) the most secure method(s) of creating a wallet.
As long as your private keys never touch an online machine, and you've created these keys in a secure way, you're setup perfectly.
By the way: if your machine holding your private keys never ever touches the internet (remove network drivers, or even network hardware), a firewall isn't needed, nor can keyloggers harm you