That will get you the basics. Problem is AVRs like Denon have about 300 additional commands that aren't on the original remote. Same story for discretes on most devices. Gotta import codes for those or learn them from a JP1 remote.

Another problem with learns is they aren't perfect. And they may not have the right toggle bits or repeat behavior either. Learning 40+ commands per device is also pretty time consuming compared to entering/importing a few codes.

For all of the above reasons, learning is my absolute last resort.