So basically speaking, if someone needs a DP using a character without the aforementioned restrictions they need to do either method A (623+Button) or E (623+Button6 done at a slightly slower pace, but not slow enough that the DP input wouldn't be recognized in other games for example Extend) right?
Apparently it doesn't look like a glitch if that's the case, looks like they are just trying to test a way to improve the DP inputs and no one noticed it on Arcade because Sticks have better input precision.