OK. Here are the rules and the decisions the refs needed to make:
Rule 10, Sec 1, Art 15.
Illegal contact caused by the swinging of the elbow(s) that:
a. Results from total body movement is a common or flagrant 1 personal foul;
b. Is excessive per Rule 4-18.7 is a flagrant 2 foul; or
c. Occurs above or below the shoulders of an opponent is a common, flagrant 1 or flagrant 2 personal foul.
Rule 4, Sec 15, Art 2, Paragraph c.1
Flagrant 1 personal foul. A flagrant 1 personal foul is a personal foul that is deemed excessive in nature (unwarranted or too much)and/or unnecessary (avoidable, uncalled for or not required by the circumstances of the play), but is not based solely on the severity of the act. Examples include, but are not limited to:
a)
b)
c)
d)
e)
f) Illegal contact caused by swinging of an elbow that is deemed excessive or unnecessary but does not rise to the level of a flagrant 2 personal foul (See Rule 4-18.7);
Rule 4, Sec 15, Art 2, Paragraph c.2
Flagrant 2 personal foul. A flagrant 2 personal foul is a personal foul that involves contact with an opponent that is not only excessive, but also severe (brutal, harsh, cruel) or extreme (dangerous, punishing),while the ball is live. In determining whether a foul has risen to the level of a flagrant 2, officials should consider the following:
a)
b)
c)
d) Any contact by the offending player to the groin area of an opponent which is not clearly accidental;
Rule 4, Sec 18, Art 7
The following shall be considered not only excessive, but extreme swinging:
a. When arm(s) and elbow(s) are swung about while using the shoulders as pivots, and the speed of the extended arm(s) and elbow(s) exceeds that of the rest of the body as it rotates on the hips or on the pivot foot; or
b. When the speed and vigor with which the arm(s) and elbow(s) are swung is such that injury could result if another player were contacted.
The first decision the ref has to make is whether it was a foul. The ref called a foul on the floor as per rule 10-1.15: There was illegal contact caused by swinging the elbows.
The second decision the ref has to make is whether the foul was a flagrant foul. Per rule 4-15.2.c.1.f, the refs determined the contact caused by swinging the elbow was excessive as defined in rule 4-18.7. Because he cradled the ball in one hand and swung the other elbow, the movement of the elbow was not part of total body movement (the speed of the elbow exceeded that of the rest of the body).
Once determining the foul was flagrant, the next decision is whether it is flagrant 1 or 2. And this all comes down to whether he made contact to the groin. The refs had already decided the contact was not accidental; the swinging of the elbows was not incidental to his body movement. So once they see that the contact was to the groin they have to call a flagrant 2 foul as per rule 4-15.2.c.2.d.
If the contact was to the chest, it is probably a flagrant 1. But by rule, contact to the groin is automatically a flagrant 2.
That doesn't mean Langborg is a dirty player. His move wasn't a Herb Pope or Xavier Johnson ball grab. But he hit Davis in the groin, so it is an F2.