His example isn’t perfect, but he’s on the right path. You can definitely come up with this stuff on your own.
The only issue here is that you ignored recovery on Move KD. If you knockdown, and it takes 60F for the opponent to wake up, you have to remember that during the first few frames of that 60, you are still recovering from Move KD. So when you’re developing this stuff, you have to figure out what frame at which you are free to move in this process, then add the whiffed move for timing, then the jump.
As for landing frames, if you attack in the air, there are two frames after you land, during which you can’t do anything. After those two frames, there are another two frames during which you can’t do anything, except block.
So in a safe jump, as was explained, if executed perfectly, on the first frame that your opponent is up from the knockdown, you’ll be in the air in the last frame of your jump. On frame 2 of your opponent being up, you’ll be in your first landing frame. In frame 3 of their wake-up, you’ll be in your second landing frame, still unable to do anything. That is why 3F reversals will hit here.
You can block a 4F reversal here, and a 5F reversal as well, but that’s all you can do with them. That’s why you can’t OS 5F reversals. You can only block it, because your OS’d move won’t come out since you can only block in your 4th landing frame. 6F reversals, and up can be OS’d because you should be out of your landing frames by the time they hit.
Umm yeah… a little more info than you asked for, I guess… but it helps to know as much as possible.