I know there are no fouls called "reaching" and "over the back" but the phrases themselves can describe illegal contact.
(Disclaimer 1: please dont tell me, I already know, I wont use those terms and I will follow the approved terms and signals from the book, I understand that).
"Over the back" is just a push as a result of a player violating verticality and making contact that disadvantaged the player in front of him. Now that is pretty difficult to say. "Over the back" is easier. "Push" is easier still. But "push" described a whole host of conduct. "Over the back" describes this specific act that is a push. The problem with "over the back" is the mis-interpretation taht simply going over someones back without contact or disadvantage or violating verticality is a violation/foul. But that doesnt mean we as officials cant use the term to describe a particular type of push.
Similarly, "reaching in" is illegal use of the hands with contact that caused a disadvantage to the dribbler or advantage to the defender. But "reaching" describes a particular type of illegal use of hands. Again, as with "over the back" the problem is that coaches dont understand what it means.
I dont think we should stop using a phrase that has meaning just because coaches dont understand it. Heck, we'd have to throw out 1/2 of the normal rules if that was our standard
I can also think of a time when you might want to say "reach" (though not over the back) instead of "illegal use of hands".
(Disclaimer 2: I understand and agree that we should only signal and say teh official calls and signals).
Its not like these arent foul situations. They are (when defined correctly, not as coaches often define them). We are just using colloquial phrases to describe them.
(Disclaimer 3: Again, I agree that when calling and signaling the foul in a game we should only use approved signals and phrases).
My only point is that those terms can be useful for discussion, so long as their meaning is understood correctly (as with anything else). Lets not throw out the baby with the bathwater.
Clark