The case play is spot-on
 

The case play says it all. This is a block. This is exactly what the Fed wants us to call. I don't like anymore than you. Belive me, I don't. But we have to call it the way the Fed wants. Do you not agree that the case play is exactly the same scenario as the OP? If so, then you have to agree this is a block. If you are going to allow the defense to be out of bounds on this play, then you have to allow the offense to step on the line to avoid contacting a defender who is near the line but not on it. We can't give the defense an advantage the offense doesn't get. We can't give them more space on the floor than the offense.

Okay lets come back to earth.
 

I think we are stretching

almost everyone here agrees that you can not just bowl over the defender no matter where he is, it the contact by the ball handler is excessive the foul would be PC, and infact you could go to another extreeme and say intentional.
that is not the intent of the OP,
What we are referring to here is -a player going to the basket in the course of a normal drive who contacts a defender who has his foot on the line, there is enough contact that it can not be deemed incidental and requires a whistle.
So other than a blarge what have you got?

No, the case play is not exactly the same. The case play specifically refers to LGP; which is completely irrelevant to a stationary defender.

Again. The case play has NOTHING to do with a stationary defender. It is all about LGP. And by definition, to have LGP, a defender must be inbounds.

We're discussing a stationary defender, so the case play is completely and entirely irrelevant.

I don't see how, with your approach, you can do anything but an intentional or flagrant on the offense. PC doesn't seem to be an option.

Yep...if a person is arguing that stepping on the line makes that player's position "illegal," then a PC foul could never be called. Either a PC foul is an option or it's not.

If it is, then all the "normal" rules should apply, and that includes that an offensive player cannot displace a defensive player.

The case play is relevant
 

No where in the case play does it say the defender was moving at the point of contact. You are inferring movement.

If you are sure the player left the court <B>on purpose and with specific intent</B>, then yes, it's a violation. The examples given on this violation are pretty clear - running around a screen OOB, or stepping out of the lane OOB to avoid a 3-second call, all seem to show clear intent to be OOB. I also know the Fed. has made it clear that momentum carrying a player OOB is acceptable. So if the defender was simply trying to get in front of the offensive player and their momentum caused them to go OOB, then there is no violation. So, unless you can show me the defender stepped OOB <B>on purpose and with specific intent</B>, then I've got to assume their momentum carried them to that spot, which eliminates that particular violation from this discussion.

Which brings us to the case play mentioned, 4.23.3B - this play has to do with LGP specifically. Notice the play says the defender obtains LGP, but is called for the blocking foul because they did not maintain LGP at the time of the contact, not because the defender violated by being OOB. That tells me the only issue involved in this discussion is LGP.

So, can an offensive player be called for a charge against a defensive player that does not have LGP? Sure. Can a stationary defensive player, without LGP, be called for a block, when the offensive player initiates contact? I would like to see the rules backing for that one.

No, I'm not. The case play is specifically about legal guarding position and says the block is called because the defender has not maintained LGP. No inferences needed, and nobody is going to disagree here.

But the scenario we're discussing does not require LGP, so you can toss that case play.

Thanks, M&M. I can't type enough to say all that right now. Those are exactly my thoughts on this play.

In the case play, B1 has obtained LGP, which means they must be completely inbounds. Then B1 "stays in the path of A1, but has one foot touching the sideline". How did B1 get from LGP to "one foot on the sideline", without movement?

I'm confused by your post. Did you just answer yourself?

And, I disagree with your conclusion. If the defender needed LGP, then it's a block. If LGP was not a factor (as in your examples with an extended arm or a stationary defender, etc) then if the player is at his spot before the offensive player, it's a PC foul.

No problem.

How did your finger get injured? Were you trying to flip off your CO?

I'm not tossing the case play
 

The case play is relevant. What will you call if B1 gets to the spot a split second before A1, but B1 is out of bounds? What if the displacement isn't violent, but A1 contacts B1 in the torso. I've got a block, because the defender is not entitled to that spot on the floor. He doesn't have LGP, just like in the case play.

I'm enjoying this debate, by the way! Its one of the best I've seen in a while!

That's just it. LGP isn't relevant if he's stationary. If he's moving, and LGP is an issue, then it's a block.