Because AO threads never go out of style.

[Stuntman]

For example, I understand that the original reason for movement OAs is so that the PCs cannot just rush past the guards and kill the king. The entire reason for the rule at all is to protect the backrank in a turn based sequence game system (typically protecting the PC squishies from monsters getting past front rank PCs). It has zip, zilch, nada to do with lowering one's guard. That is nonsense fluff to describe game mechanic balance and always has been.

Unfortunately with 4E, one can take a wide detour around the guards and still get to the King. So, the OA movement rule still exists but the main reason for its game mechanics existence is less important now. There used to be a shortest path past the guards. Now, that doesn't exist unless the guards cover the entire area. So, the game designers had to add the concept of Fighter marks in order to attempt to offset this deficit. It helps some, but it's still not as strong as the original rules which forced either an OA or extra movement regardless of who was in your way.

This is not the proper way to protect someone in the back ranks. If the enemy and your charge (the person you are trying to protect) are directly verticle or horizontal to each other, you should not place yourself directly in between the enemy and your charge.

The proper way to protect your charge is to move adjacent to the enemy. That way, the enemy must provoke an OA if he wants to move past you or have to waste a shift to move away from you and need more movement to get to your charge.

Another way to protect your charge is to ready and action to charge (the standard action) the enemy when he gets near your charge (the one you are protecting). This way, works well because the enemy is likely in the middle of his move action and must either not attack your charge or provoke an OA if he wants to continue and attack your charge.

The diagonal movement rules force you to do things differently, but still allows you to protect your charge and force the enemy to waste movement or provoke and OA when you are defending someone.

 

[N0Man]

I think it's kind of a mix. I think there are a few fluff reasons why these remained, but I think it is primarily for gamist reasons.

I'm ok with that though. I still see them in 4E games, but they probably are easier to avoid. On the other hand, I think 3E sometimes went a little overboard with provoking. Many character builds seemed to revolve around forcing provokes and punishing them, often in ridiculous ways.

I prefer how they are now, a garnish rather than a centerpiece.

 

[unan oranis]

KD; my remarks to now have been some-what insulting, I regret straining my forum conduct.

 

[Piratecat]

KD; my remarks to now have been some-what insulting, I regret straining my forum conduct.

Good timing; I was just swinging by to say the same thing. Thanks for apologizing.

 

[KarinsDad]

KD; my remarks to now have been some-what insulting, I regret straining my forum conduct.

No worries. I do that kind of stuff all the time.