"Come" is also not basic. It's virtually impossible to directly transfer an on-leash "Come" from 5 feet away to a 30 yard, off-leash "Come" in a distracting park. Why? It's because a fast, proper "Come" is also a complex behavior that requires the dog to have solid impulse control. It requires reward manipulations and high criteria. It requires first teaching a "whiplash" head turn, followed by running towards you, followed by frequent practice in all situations:
So, when we promote the "Basic 5" as pillars of responsible dog ownership, do we really want to encourage sloppy "Heels" and unreliable "Comes"? Or are we trying to promote something else, something different?
Most dog behavior problems aren't due to not knowing the Basic 5 obedience commands. Rather, dog behaviors stem from a miscommunication between the dog, the trainer, and the environment. Behavior problems are often solved by teaching the dog impulse control and to focus on the handler. It has very little to do with teaching 5 obedience commands. It has everything to do with teaching the dog how to think. So, instead of focusing on teaching Sit/Stay/Down/Come/Heel in 6 weeks, we dog owners and trainers should focus on teaching our dogs how to think through shaping, positive reinforcement, and negative punishment.
Practice makes progress!