It's honestly better just flawless blocking gaps. Way less risky than throwing out this goofy ass parry.And sometimes you will get hit.
Like you, I also use it when I read wakeups.
I use it for stagger heavy characters. People who play characters like Kung Lao, Scorpion, Liu Kang, etc. love to fucking stagger. So you can take the first round and watch their patterns. Scorpion does F3, pauses, F3 again....even if it's frame perfect you can slip in a Mime Time after the first F3 and take 28% of their life. My favorite is Liu Kang though. He eats that shit all day. You can even Mime Time in gap between F43 and U3. Hard read though.
I also use it if I see a lot of D1 counter poking. Do a string, end with Mime Time, they go to poke and eat shit. Characters with fast mids like Kang and Jacqui will sometimes counter poke with their fast mids. You'll catch that shit too.
Lastly, sometimes when I'm just within the range of their best mid, I toss it out. Dangerous, I know, but it does work. This one I barely use.
I really wish Mime Time was like 6 frames. Then Johnny could hit a lot of the gaps in this game. Oh well...