Sometimes.
Jab is also used as a setup, or even a mindgame. If you can get them to DI wrong, or catch them off gaurd, it works well for whatever. If they DI away, then just laser or sometimes even Fsmash them (high percents). If it's a low percentage, you can jab them to either shine, jab again, or grab. This is all assumed that the jab hits.
If they shield it, I believe they have a small frame to attack you or grab you between the 1, 2 Jab. But I'm not exactly sure. If they spot dodge the first jab, they will more then likely get hit by the second.
I personally always go for the jab to shine since it's the fastest and gives them little (or none? i'm not sure. fram data... pfft.) time to do anything if they're shielding.
Also, you can jab to run away if they're shielding
![Laugh :laugh: :laugh:](/styles/default/xenforo/smilies/laugh.gif)
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