http://www.8wayrun.com/f6/frame-data-and-you-a-laymans-guide-t3702/
http://www.8wayrun.com/f6/frame-of-reference-t1536/
These are two threads about frames. Generally you just compare what you wanna test with the frames of reference.
I found that last PO 8K thing out while trying stuff on the Dummy in practice mode.
I programmed the dummy Taki on 1 action stand normal, 2nd action start command. I recorded 2A as command to see what PO stuff will evade or beat a 2A after which move to PO.
For example after a 33_99A PO on hit, a PO 8K will beat their 2A and when my PO 8K hit the dummy who was trying 2A i got the CH and i saw that the Hit Stun looked different from the normal hit.
Then i switched the counter hit on in the practice pause menu, and set the Dummy to 1st action stand normal, 2nd action start command (i recorded a fast punisher as command, with Soph, 236 B because that was better than Taki's punishers due to range)
So when i CH the dummy with PO 8K and he tried to Punish with the fastest punisher, but couldn't, i knew PO 8K was safe on CH.
You can just switch Counter Hit on and off in the Practice Pause Menu and then do moves to test their recovery on hit, CH or block, by programming the Dummy to 1st action stand normal/stand guard, 2nd action start command, record attacks and see what beats what after what.
And you can do it the other way around by programming the dummy to do certain sequences of moves and you try to interrupt. Or just to see what's punishable and how. This is the easiest way.
The Dummy in practice is your best friend in this learn how to program him to test and COMPARE stuff.
PS.: Don't use 2nd action attack, because them attacks seem to always come out 1 or 2 frames later than possible.
Always use start command and record the moves yourself.
I hope this isn't too complicated but that's how i do it. If you have further questions feel free to ask again.