Freeze! Defensive Techniques Using Proximity Block

When I play JP against Kimberly, I often struggle with corner defense.
Besides having many Gimmicks, Kimberly's walk back speed is very fast. When I want to Reversal, the following scenario often occurs:

I worry about her walking back into a Fierce or a slide. Even if I know she is -2 after a Medium Punch, I'm still afraid to press a button, fearing that her walk back will cause my Medium Kick to whiff because the Range looks very tight. But in reality, she cannot walk out of it.

In the 0.5x speed video, you can see that as soon as the Medium Kick is pressed, Kimberly stops walking back.
This is due to a game mechanic called Proximity Block—that yellow box at the bottom.

Enemies within the yellow range are forced to stop walking back. JP's Medium Kick Proximity Block appears on the very first Frame. This means the moment Kimberly finishes her attack, she will be frozen in place even if she tries to walk back.

JP's Medium Kick takes 8 frames to become Active, but it can stop Kimberly from a distance on the first frame. Without this mechanic, Kimberly would only need to walk back for 6 frames to leave the Medium Kick's attack Range and land a big Punish. (You can see what happens without this mechanic by setting JP to counter-attack with a few frames of Fuzzy delay after a Block to see the whiff.)

The most obvious example of using this mechanic is Ryu's Forward Fierce. Its Proximity Block is particularly long and appears on the first frame.

This leads to hilarious scenes where Kimberly, despite finishing her attack, cannot walk back and is simply frozen in place by Ryu.

You can use this mechanic to counter-attack when the opponent is at a certain distance.

Take Ryu vs. Ryu for example: after an opponent lands a Fierce at tip range, they usually won't press more buttons because the distance is too great.
At this moment, you can use Forward Fierce to freeze them in place. Even though Forward Fierce is slow to become Active, the opponent usually won't expect to need a button for a Counter Hit. It's more common for them to try pressing something and end up getting hit by a Counter Hit instead. Forward Fierce only takes 20F to become Active, making it very difficult to react to and then press a button for a Counter Hit.

This is especially strong in the corner. Usually, blocking an attack causes pushback, but there is no room for that in the corner. For instance, Ryu's Medium Donkey Kick normally kicks the opponent far away, but not in the corner. Medium Donkey Kick is -8F. Even if your buttons can't Punish it, using a move with long range and Proximity Block can freeze him in place.

Note that Proximity Block cannot prevent jumping. This means Airborne moves like Cammy's Divekick can still turn defense into offense for free in this situation.