Also a couple of things that spring to mind:
1. DF4EX is a more optimal combo extender usually but using MB Hellsparks for this specific combo seems to give 1% more. However using DF4EX allows you to do NJP, JI2 which gives slightly more advantage than NJP, JI1.
2. This setup is asking a meter reliant variation to spend 2 bars to not even guarantee 32%...I don't think it's worth it unfortunately.
3. Where did you get that J1 was +50 on hit? It's definitely not lol. The only thing to do with j1s that are +50 on hit is a raw NJP which isn't what you're ending with in this setup.
Although while in the lab I did find some completely different tech so thanks for making me go into the lab I guess haha.
Yeah but you're reacting with a backdash, not guessing. It has 58 frames of startup so there's more than enough time to recognise when it's coming and backdash accordingly. Even if you delay the input he'll still be able to react to 58 frames.