This only allows access to the raw packets that are being broadcast over wifi/cell. (It's like tcpdump, if you're familiar with that.) For stuff sent encrypted over the internet (https/imaps/etc), it's pretty much useless. If stuff is being sent unencrypted, there are other means of looking at it anyway.
The "pairing" refers to when you connect via a USB cable and say "trust this computer". (The iOS device must be unlocked.)
An encrypted copy of the some keys are sent to the computer. These allow the iOS device to decrypt data that normally can only be decrypted after the passcode is entered. (Making it possible to back up the device without entering the passcode.) Those encrypted keys can only be decrypted by a trusted computing module on that specific device. So you are kinda screwed if someone has both your laptop and your iphone, and they have Apple-level access to the iphone. I recommend using file vault or other full disk encryption to protect your laptop.