In online flying games there is immediate reinforcement of bad behaviors and habits.
From the first sortie the guns are available.
In the real world a pilot goes through an extended period before he ever gets anywhere near pulling a trigger.
Starting from primary flight training the military pilot is building skills that have nothing to do with shooting but everything to do with winning the fight.
Formation flying is the basic laboratory for building an understanding of the geometry of the fight.
Every fight is an exercise in trying to join into formation on the target or prevent the enemy from joining in formation on you.
In the real world, the neophyte is given a target that is not maneuvering to deny him. He learns spatial relationships and techniques on a target that is actively helping him solve his distance and closure problems. Later the target is not actively helping or hurting. Only after the student has mastered formation joins from every angle on a friendly is he thrown into the pit with a target seeking to deny him his solution.
In online gaming a training structure that recognizes this fact greatly aids the student. Since we don't have friendly collision we don't have to get very deep into formation technique but a student that cannot effectively join on a non maneuvering target needs to hone those skills before embarking on an attempt to do the same against a maneuvering bandit.
It is a solid base to build on and should be the first step in evaluating a new trainee.