Memory saver for changing altenator

I’m getting ready to change alternator and the instructions say to use a memory saver…is this absolutely necessary?

 

Nope, disconnect as any other repair. It’s just a generic instruction I presume

 

It may refer to a power port battery whatchamacallit to preserve your settings when you disconnect the battery. But it is only helpful if there is power there with the key out of the ignition.

 

If you had one it would prevent you from losing your radio presets and such. It's optional.