I am jumping into the thread late but I would like to comment on NFHS CB Play 4.19.12 which is the exact play in the OP.
1) This play does happen from time to time (and in 43 years for officiating I have seen this type of contact happen; and it is not as uncommon as some people would like to believe. But is it called as in the CB Play? The answer no. I cannot ever (for the J. Dallas Shirley fans, did you notice how I avoided using the word "never",
) seeing a FMF called in this situation.
2) BUT!! There is one time that it could be called as in the CB Play but the contact is extremely rare. If the second PF is an "undercut" then both fouls have to be charged and penalized.
I cannot remember the last time I have heard anybody on this Forum talk about an "undercut" foul. For those to do not know what such a foul is, I will describe it. It is when a defender slides into the path of an airborne player but is not facing him in an attempt to take a charge (which would be a Common Foul) but has his back to the airborne player such that when the airborne players legs hits the defender's back the defender bend forward and causes the airborne play to rotate forward about his center of mass and land more or less on his hands and knees. The resulting landing can cause broken wrists and more. It is at the least an Intentional PF and can very easily be a Flagrant PF.
If were were revise CB Play 4.19.12 to change B2's foul to be an undercut, that I would have no problem with both fouls being charged and penalized because B2's foul is at the least an IPF and very easily a FPF.
Fortunately for the game of basketball I have not seen "undercut" foul in close to 30 years and the last time I saw one I ruled it FPF.
MTD, Sr.