Completely clean reset of Mac—does Internet Recovery reset Recovery partition
The whole point of Internet Recovery is to allow reinstallation of the OS when all data on the internal storage is lost, including the Recovery partition.
However, some people have had trouble with some models of Macs not connecting to Apple servers. It's certainly worthwhile making sure you've got an external bootable install media for emergencies.
Also, there's not really any point in 'resetting' the Recovery partition and the entire disk itself: erasing the system/user volume and reinstalling using the Recovery partition will suffice to put the Mac back to a 'brand new' state.